In honor of Women’s History Month, The Root pays tribute to African-American women working in the fastest growing field around the globe. While their numbers may be relatively few (pdf), they are making great strides, using their science, math and engineering degrees to amass impressive digital portfolios. Jobs in science, technology, engineering and math (STEM) are projected to expand at more than double the rate of the entire U.S. labor force through 2018, according to a recent STEMconnector report
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Christina Lewis Halpern (Courtesy Christina Lewis Halper); Laura Weidman Powers (Courtesy of Stanford University); Angela Benton (Courtesy of Angela Benton)
Didn't matter where I was, I kept rubbing my eyes. I thought a space capsule had landed. Simple and intriguing form, round, squat, cone for a roof and a dome or chimney vent. A fabric weather wrap secured by bands around it's waist and a single door. Like an African mud hut but portable, durable and movable. I thought of Indian Tee-pees, Bedouin tents and the tin shacks of South Africa or any other place where the nomad life was a necessity.
Nah, this is romance, you walk thru the door of the space capsule into a world of carpeted floors, wall hangings, incense, a small stove fire, coffee, a stew, sitting on pillows, heads and bodies wrapped in colors, words of gracious hospitality and a respect of boundaries inferred yet seduced by the mystery of desires' expectation.
A house is like entering a mind, world as it is on the outside, inside a place of limitless measure contained in it's confines. In Central Asia the 'Yurt' is like that and it doesn't matter if made from sticks and animal hides or the most high tech materials from NASA, it evokes an air of transportable roots yet a solid stay. I consider the humble yurt the tent of tents, the hut of huts. I've seen them on desert plains, snow tundras, wood clearings, lake decks and on the flat roofs of buildings that scrape the sky...............!
How soon we forget this was once all theoretical, now it's how we play our CDs and DVDs, programming our electronic devices...those were lofty days, when we looked forward to the future and the hope in science. Dr. Townes' light has dimmed, but not his lasting impact, a kind of immortality that is worth striving for. As a nation, we cow in fear of the light science brings to our previous ignorance; we're always longing for the past; looking ever backwards to a utopia that never was, simultaneously ignoring a future that we could create.
The US physicist Charles Townes, who shared the 1964 Nobel Prize for Physics for his work that led to the development of the laser, has died at the age of 99. Townes played an integral part in the race to make the first laser by developing its forerunner – the "maser" – which could produce and amplify electromagnetic radiation in the microwave region of the spectrum.
Townes' key work began while he was at Columbia University in the early 1950s, when he proposed a device that could produce coherent electromagnetic waves through amplification by stimulated emission. He coined the term "microwave amplification by stimulated emission of radiation" – or maser – although Townes was not the only person to have the idea. Independently, and at a similar time, Nikolay Basov and Alexander Prokhorov of the Lebedev Physical Institute of the Russian Academy of Sciences, and Joseph Weber of the Catholic University of America, had also been working on the theoretical framework behind the maser.
Topics: Diversity, Langston Hughes, Martin Luther King, Speculative Fiction
Of late, I have been thinking of stories and diverted eyes. This is an encore as I've used a form of the title before in a similar post.
We've told stories for our own entertainment and for the dispensation of knowledge of our culture. We've told stories in poetry, prose and fiction: classical and science fiction. We've told stories as many people - the sea of humanity that we all belong to - have told stories in the past: to preserve histories; to teach lessons; to make people love us as us; more importantly, to uplift and love ourselves.
The physics and science posts will occur at their usual time: 7:00 AM EST; 4:00 AM PST. I actually have enough STEM material for February 2016! It will be hard and tempting to not publish it before then.
The posts for the month will be on the Diaspora's contributions to STEM as well as speculative fiction, A.K.A. science fiction. I will start with someone you may or may not know and intersperse that person with persons you also may or may not know. The Internet has freed many to not seek the approval of mainstream publishers, though many who started their literary journey as independent have; some stayed entrepreneurs and prefer it. As I said, I've been thinking about stories, self-images and stereotype threat.
Carter G. Woodson had a whole other purpose for what was then known as Negro History Week, then Negro History Month, now African American/Black History Month:
"If you can control a man's thinking you do not have to worry about his action. When you determine what a man shall think you do not have to concern yourself about what he will do. If you make a man feel that he is inferior, you do not have to compel him to accept an inferior status, for he will seek it himself. If you make a man think that he is justly an outcast, you do not have to order him to the back door. He will go without being told; and if there is no back door, his very nature will demand one."
I prepared this post 20 January and scheduled it to appear on 1 February. All the other posts regarding the month were so pre-planned in a similar fashion. It allows me to then read physics/STEM posts; keep up with my own studies and speak on hopefully up-to-date topics as I celebrate the month. It is also frankly, a pacing that keeps me from getting too exhausted.
For those that must believe in Bigfoot, fairies, pixie dust, racism, unicorns and xenophobia, please feel free to carry on personal delusions. You are free to divert your eyes elsewhere this month: I won't be talking to you, straightening your backs or changing your minds. I will be telling of triumphs and stories in science and modern myth for the interested, the intelligent, and those that want to stretch their knowledge of their fellow humanity, but more particularly as a group: the young, our collective futures in this country and world.
Just as (Dr. King and Langston both say below), we are free...within ourselves to straighten our own.
"Change does not roll in on the wheels of inevitability, but comes through continuous struggle. And so we must straighten our backs and work for our freedom. A man can't ride you unless your back is bent."
Dr. Martin Luther King, Jr - and, a seldom-quoted riff (embed) below...
Let the blare of Negro jazz bands and the bellowing voice of Bessie Smith singing the Blues penetrate the closed ears of the colored near intellectuals until they listen and perhaps understand. Let Paul Robeson singing "Water Boy," and Rudolph Fisher writing about the streets of Harlem, and Jean Toomer holding the heart of Georgia in his hands, and Aaron Douglas's drawing strange black fantasies cause the smug Negro middle class to turn from their white, respectable, ordinary books and papers to catch a glimmer of their own beauty. We younger Negro artists who create now intend to express our individual dark-skinned selves without fear or shame. If white people are pleased we are glad. If they are not, it doesn't matter. We know we are beautiful. And ugly too. The tom-tom cries and the tom-tom laughs. If colored people are pleased we are glad. If they are not, their displeasure doesn't matter either. We build our temples for tomorrow, strong as we know how, and we stand on top of the mountain, free within ourselves.
Posted by Greg Denmark on January 30, 2015 at 2:02pm
The fact that this is a Sci Fi site means that I limit my very strong and very radical African-centered ideologies to within the scope of Sci Fi and Fantasy, which is rightly so.
This video is an exception to that.
I see a lot of Black folks supporting a narrative that we are all the same as humans and that hard work and quality will trump discrimination and a host of other false opinions. Today is one of those days where it supremely annoys me to hear it, hence this video.
Ironically, I see far too many posts on Facebook that strays away from Sci Fi and I, on occasion, support those who ask the question, "What does this have to do with SciFi?"
Also, of great irony is the person in the video. But, I put this up here because these same "we are the world" folks will write it off if it does not come from a White person. Many will STILL write it off, but, oh well.
While reading a work, be it short or long form, one character attribute that should become immediately apparent is the political stance of that character.
Whoa, you say, politics? I am not writing some political work, I am just telling the tale of a simple space marine who battles hyper-intelligent alien bees trying to invade our dimensions (Ed: Yes, please, tell me more...).
Authors, especially the new or under-read, have a tendency to argue the studious un-political nature of their work. The reasons may vary. Perhaps they do not want to upset potential readers and customers. And why not, Orson Scott Card went from beloved author to homophobic bigot in a lot of minds based on religious beliefs that informed his political position. (even this criticism pales in comparison to the amount of real and digital ink spent on the fascist nature of Ender's Game itself.)
Alternatively, perhaps an author has a general uncomfortableness about speaking on political issues or a genuine desire to write tales having an apolitical affect.
However, it is impossible to write good, character driven, para-fiction without having those same characters take a political position. It is impossible to build a successful world for your characters to inhabit without having a political position.
Situating a character into the world you have built requires more than just placing motivation in her head and obstacles at his feet. You have to ground your characters within the philosophical framework of the world they live and the options they have available. In the same way that it is impossible to ignore the economic standing of your character (try reading Jane Austen and not come away with a useful understanding of the rentier economy of Georgian England), it is impossible to untangle the politics of a character from their motivation.
Politics includes more than where one (the author or the character stand) stands on the hot button social issue of they day. Politics means a political outlook. A particular view of the world as it is seen through the character's eyes (if it is a first person narrative) or multiple character's experiences. The political view of the character does not need to be endorsed by the author, but the author does need to explain the political position of the characters.
Is your hero battling a dystopian government? Why is the government horrible? Is it the fault of the government, or some outside agent that is causing grey skies and sad people. If it is the government, why is it doing this? Sometimes in the rush to have people battle on post-apocalyptic roof-tops, authors forget to do the hard work of building the foundations of conflict. If only America has fallen into ruin, Why? What was it about the politics of America that caused this downfall? What policies does the government implement that make it evil, or good? Unelected dictator? So your hero is a pro-democracy advocate? Elected counsel of evil Corporations? Complete Anarchy and Individualism and ultra-property rights? Collective action, Forced Community? It is impossible to have your characters stand against something without also standing for something else.
To build great characters, you need to build a political dossier along with a physical and economic dossier. Once you character has a stance on the issues, not of your day, but of her day, then the conflict from those stances becomes easier to envision and capture.
I find it crazy that in 2015 there still seems to be a problem with casting dark skinned woman in major roles.what's even crazier is that we're having this problem when it comes to casting Africans, especially with all the emerging talent of African descent. I mean isn't Storm an African? I get it, social engineering and euro-standard of beauty being the default, but aren't Black People sick of this ish yet? it's like we just get happy they didn't cast a white woman. I'm going to stop here before Jarvis bans me. One thing I know is I'll catch this one on bootleg. Let me know how yall feel about it.
CALL FOR SUBMISSIONS… DEADLINE! FEBRUARY 1st, 2015 (for FEBRUARY 20, 2015 publication date)
“O.T.H.E.R.” SCI FI WINTER 2015
Over The Horizon Empires Rise OTHER Sci Fi is a Magazine/Journal is dedicated to the creation and promotion of SciFi, Speculative Fiction, Horror and Fantasy works of Epic proportion focusing on and featuring diverse characters, civilizations, subcultures, worlds and universes in alternate and crafted realities.
SUBMISSIONS We are looking for works to be included in the 2015 Winter magazine with publication scheduled for February 20th, 2015. There is no "specific" theme but Valentine and Winter themes are not discouraged. Please hit the link to view the particulars.
Topics: Civil Rights, Day of Service, Four Little Girls, Martin Luther King, The Price
President Obama has signed a bill that awards the Congressional Medal of Honor to the four little girls killed in the 1963 KKK bombing of the 16th Street Baptist Church in Birmingham, AL.
The girls – Addie Mae Collins, Cynthia Wesley, Carole Robertson, and Denise McNair – were killed on Sunday morning when members of the Klan planted dynamite in the Church’s basement.
Their deaths shocked the nation and the world, and stands as one of the most violent, horrific events of the Civil Rights Movement. Info and Image Source: Black Youth Project
By 1963, homemade bombs set off in Birmingham's black homes and churches were such common occurrences that the city had earned the nickname "Bombingham."
In the spirit of a "Day of Service," I served meals to the homeless at Beulah Baptist Church in Poughkeepsie, NY with my brothers of Kappa Alpha Psi this past Saturday. We fed over 200 persons (estimated) in assembly line fashion: chicken, rice, green beans, bread and a dessert. It was a multi-ethnic group, and included many families. For the most part, they went for the meals only. It was personally rewarding (though tiring), as I will be working through the morning and evening on the official holiday today.
This occurred September 16, 1963, a day after my mother's 38th birthday. I would have been a year and a month old; a month from the missiles of October's anniversary (we had teetered on the precipice of Armageddon - that was almost 10 months shy of my ONLY year); President Kennedy's assassination in Dallas, Texas the very next month. The times probably worried her, I'm sure.
We tend to forget the price paid by those who in an instance found themselves on the front lines of a battle for fairness over supremacy; freedom over de facto slavery via Jim Crow.
We tend to forget that soldiers aren't muscled, mighty men. Sometimes, they can be four beautiful little girls in the safest place they could possibly think to be - in their house of worship.
We also tend to forget that icons like Dr. Martin Luther King we admire now was vilified by some of his own - culture and clergy - and the extreme right of the time wore white sheets instead of (now) Armani, pin stripes and Prada.
We also forget in living rooms of complacency, flat screens, MMORPGs and comfortable backsides, only interrupted by the occasional level of violence that used to be so...commonplace, that sadly perhaps is becoming so again. It need not be someone you know to act on the behalf of others. Being human, compassionate and common decency should be more than enough.
May today be a Day of Service for you as you see fit to express it.
Topics: Apathy, Diversity, History, Oscars 2015, Selma, Voting Rights
I spent Friday watching "Selma" in tears from the haunting images, graphic displays of violence that was (is?) a part of our country on quite a regular basis in the 1960's. During the time of the Civil Rights Act (1964) and the Voting Rights Act (1965), I was 2 and 3-years-old respectively, too young to be of any good to the movement and merely a worry for my activist big sister.
I think a lot about my big sister in movies like this. She would have been one of the young people that got on "freedom ride" buses and put her life on the line for equality, or as she says now, everyone's equality, women, immigrants, LGBT. I remember her arguments with our parents about her safety. I remember praying I'd see her again. I remember crying a lot.
As I said (without giving away spoilers), my wife and I spent most of the movie in tears. I doubt if either my sister, mother-in-law or a lot of seniors in my family will want to see this movie. For them, it brings back painful memories.
If "demographics is destiny" - the mantra for the year 2042 - then, at 6,028 voters of which 94% are so-called "white"; 76% male and the average age 63 years, it's a pretty forgone conclusion that our stories were not going to get a mention above "best picture" and song; our actors were not going to get an Oscar nod. Also of note in that demographic, their sentiments of the time would have been shaped by their environments. Since we don't know where they lived before residing in "liberal" Hollywood, their view of Selma's value in lieu of #BlackLivesMatter and the recent, gut-wrenching atrocities of Boko Haram is an interesting contrast compared to how they all jumped on the #JeSuisCharlie bandwagon so quickly...and easily. A group of 5,666 and male gender of 4,581 pushing into senior citizenry don't likely have heroic memories of the 1960's since there was clearly two sides of the debate - depending on their families' politics at the time - they could have found themselves on. That makes for an academy clearly lacking diversity, either ashamed or indifferent.
What exactly is an "Oscar," and why does it matter? This is a self-contrived public pat-on-the-back by the industry itself. Whether you look at it or not, it is a vast infomercial on the movies you could have seen and didn't. You'll pay the $11.50 per person (New York prices) and the equally outrageous price for popcorn; you'll order it on pay-per-view; download it on bootleg: win-win-win-kinda-sorta (not).
These are OUR stories, and all of humanity's stories: it is not for us to make some privileged, self-mythologized group of "others love us" - it is for us to love ourselves, they are validated in the telling of them; everyone else is along for the ride and welcome. Our campfires required no feedback from the tribe other than applause; they are now clearly in the electromagnetic spectrum. We can read; we can write; we can act and direct; we can upload videos and audio; we can distribute on DVD and via Netflix. If Selma is anything more than an ironic juxtaposition regarding Civil Rights and Voting Rights fought for by young people and fifty years later, their millennial grandchildren being too apathetic to decide their own hard-fought destinies in the voting booth (but, up front in line on Black Friday), they deserve whatever bizarre legislation that is likely to come of this 114th congress. Opinions are fine, but action is far better, and revolutions have never been won in living rooms on backsides, nor freedoms for "consent of the governed" maintained without constant vigilance and participation. Voting, as Selma did, and the midterms' aftermath will show: matters.
An artist's impression of Kepler-62f, a planet that is in the habitable zone of a star smaller and cooler than the Sun, located about 1200 light-years from Earth. (Courtesy: NASA Ames/JPL-Caltech)
Topics: Astronomy, Astrophysics, Exoplanets, Space Exploration
Even a thin atmosphere can keep a planet spinning freely, giving it a day-and-night cycle like Earth's, say astronomers in Canada and France. The result implies that many of the planets lying within the habitable zones of "dim suns" – the most common type of star – could have terrestrial-type climates.
"It was a surprise," says Jérémy Leconte, an astronomer at the University of Toronto. "We didn't expect that there would be such a strong effect."
Astronomers have so far discovered more than 1000 exoplanets – planets orbiting stars other than the Sun – and it is becoming clear that our tiny portion of the universe could contain vast numbers of such planets. What is not yet clear is how many of these planets could actually harbour life.
Most stars, known as orange and red dwarfs, are cooler, fainter and smaller than the Sun; so to stay warm, a habitable planet must huddle close to the star. But the closer a planet is to its sun, the stronger are the tidal forces that the star exerts on the planet. These tides can affect how fast the planet spins. In extreme cases, these tides are so strong that they produce "tidal locking", forcing the planet to spin as slowly as it revolves. This means that one side of the planet forever faces the star, while the other side forever faces away, creating a world with a permanent day side and a permanent night side. The night side may get so cold that air freezes there, robbing the planet of an atmosphere.
Topics: Astronomy, Astrophysics, Carl Sagan, Sociology, Urban Planning
"We are made by the atoms and the stars… our matter and our form are determined by the cosmos of which we are a part."
"We are made of star stuff." Carl Sagan
TECHNOLOGY REVIEW: Urban sociologists have long known that a set of remarkable laws govern the large-scale interaction between individuals such as the probability that one person will befriend another and the size of the cities they live in.
The latter is an example of the Zipf’s law. If cities are listed according to size, then the rank of a city is inversely proportional to the number of people who live in it. For example, if the biggest city in the US has a population of 8 million people, the second-biggest city will have a population of 8 million divided by 2, the third biggest will have a population of 8 million divided by 3 and so on.
This simple relationship is known as a scaling law and turns out to fit the observed distribution of city sizes extremely well.
Another interesting example is the probability that one person will be friends with another. This turns out to be inversely proportional to the number of people who live closer to the first person than the second.
What’s curious about these laws is that although they are widely accepted, nobody knows why they are true. There is no deeper theoretical model from which these laws emerge. Instead, they come simply from the measured properties of cities and friendships.
Today, all that changes thanks to the work of Henry Lin and Abraham Loeb at the Harvard-Smithsonian Centre for Astrophysics in Cambridge. These guys have discovered a single unifying principle that explains the origin of these laws.
And here’s the thing: their approach is mathematically equivalent to the way that cosmologists describe the growth of galaxies in space. In other words, cities form out of variations in population density in exactly the same way that galaxies formed from variations in matter density in the early universe.
Sunny, a slight breeze, I had to meet with a guy about converting my garage into a tiny house/man cave.
The street was lined with older large homes, average city lots, all spiffied and immaculate like storefronts. Like storefronts because the sides were weathered and beaten. I pulled into the driveway, small sign said come to the back.
Beyond the end of the house sat a shed attached to a quonset greenhouse and another shed on a trailer docked to the end of the greenhouse. Strangely patterned quilts hung in a clothesline and a solar bar-BQ grill I never seen in real life. I was expecting a Martian to appear in my presents as I gazed disconnected from reality.
"The quilts are a matrix of piezo crystals and solar cells to capture sun, sound and wind energy." I didn't even spin to see whom was speaking. "The front house facade is for show, I mostly live back here now." Yoda, you must be Yoda! I blurted out. There was silence then we burst out laughing. "I've been called that. Who is that anyway?"
"We are all joined by the hip to the grid. I just thought I sip through a straw instead of gulping like it's my last day on earth." "How much of anything do I need anyway." "Besides, it's fun to do what I do with my own time and dime and not spending most on grid fees." "They give incentives to use less energy, then raise the rates because you aren't paying your share, endless game." "I am constructing a smaller house within the big house so in the winter time I won't have to heat all of it."
"In the summer I come out here, it's a minimalist paradise, I'm an urban techno native." "The stationary shed sleeps two, has everything needed for a simple decluttered life." "We live mostly in our mind so once you clean your head of others thinking, demanding, approving, and influencing, you can get on with unobstructed living."
"The greenhouse has a fish unit, veggies, herbs, I can really go shopping once a month." "The mobile shed is my travel house, I haven't seen the inside of a motel in years." "On a good sunny day, I can grill whatever, even steaks. It also has a thermo/electrical converter that makes electricity." "I charge batteries of all kinds for the whole neighborhood with my extra energy." "Too bad the hood isn't all as I but some get it and some never get anything."
I took it all in. Sitting here at home reliving that experience and complaining. Damn, I just let that man redefine my values and I've got to do something about it. I'm drawing plans for an inner house, mobile shed and greenhouse. I wonder where he keeps his light-saber?
Mythology week is coming up on the @afrophantoms Twitter account. Before I go further into detail about mythology week, let me first say that I love myths, legends and all things from the ancient world. Mythology is the reason I wanted to become an archaeologist as a kid. Eventually, I studied anthropology in college with a focus on folklore.
Growing up, myths and lore from the western world was readily available for the picking. I cannot stress how many times I’ve read Homer or the Arthurian legends. In a previous post I talked about how I took a Harry Potter class in college because J.K. Rowling makes direct references to these giant works of literature. You can read it here.
Sadly, I couldn’t help but feel lonely. These epics and myths are not my history. I can talk all day about how multicultural and ethnically diverse the ancient Mediterranean area was, but for the sake of this post I’m going to say that most of the heroes we read about had white faces.
In high school I took a world mythology class where I was introduced to the Ramayana and the love story of Osiris and Isis and Osiris’s evil, jealous brother Seth. Interestingly, we never talked about sub-Saharan African or Chinese mythology.
Osiris and Isis drakinan.weebly.com
My thirst for knowledge is the inspiration for mythology week. This is a learning opportunity for all of us. During these seven days of greatness, Asian, African, Australian, Native American and Caribbean mythology will be explored. If anyone has any myths they want talked about email me at afrophantoms14@gmail.com and like us on Facebook.
Posted by Brandon Hill on January 17, 2015 at 1:32am
So, I have a friend on Facebook who is a moviemaker and martial artist, who has been quite verbose about the recent casting of Scarlett Johansen in the adaptation of the anime classic, "Ghost in the Shell" slated for a 2017 release. This decision has sparked something of a controversy about ethnicity and movies among internet bloggers, and my friend was no exception to the rule, here.
Now, I don't completely disagree with all his views, but there are some things that have concerned me. And since this has become a very involved discussion, I felt the best way to do it was to make a video in response to his article, which can be found here. I recommend you all go and read it, and then take a look at my video response. I want to see what you think, as writers and aspiring filmmakers, about this issue of ethnic diversity.
The second video is subtitled in French, but the concept is discernible from the animation. It would be interesting to blend say, a high school French class with a Physics class: industry refers to this as cross-training or joint development; young minds are no different. Translating the video should take a little collaboration and work from both classrooms; post yours in the comments section below. Teachers: Award extra credit where applicable. Juste un petit quelque chose pour pimenter un vendredi...
History note: Today is the actual birthday of Dr. Martin Luther King, Jr. More on that Monday.
Einstein's first paper on the photoelectric effect was received March 18 and published June 9. He proposed, inspired by Max Planck, the idea of light energy in packets, or "quanta."
The Latin phrase annus mirabilis is rightly translated "year of wonders" as well as "year of miracles." 1492 saw the discovery of the West Indies by Columbus and the birth of grammar construction for modern language. 1543: the scientific revolution with Andreas Vesalius, "De humani corporis fabrica" (On the Fabric of the Human Body), and Nicolaus Copernicus "De revolutionibus orbium coelestium" (On the Revolutions of the Heavenly Spheres) in Nuremberg, Germany. It was applied to a poem written in 1667 by John Dryden, commenting on the Battle of Lowestoft fought by English and Dutch ships in 1665; the Four Days Battle of June 1666, and finally the victory of the St. James's Day Battle a month later. The second part of the poem deals with the Great Fire of London that ran from September 2–7, 1666. He wrote this escaping the Great Plague of London at Charlton in Wiltshire. The poem contains 1216 lines of verse, arranged in 304 quatrains. The reference has had many iterations and uses up to and since Einstein. Source: Wikipedia
We are now 110 years from the event that birthed the modern age of physics and technology we now find commonplace enough to take for granted by a guy in a patent office that at the time, didn't feel he was too successful. He would thankfully be proven in this instance quite wrong in his self-assessment.
"Do not worry about your difficulties in mathematics, I assure you that mine are greater."
"It is the supreme art of the teacher to awaken joy in creative expression and knowledge."
TECHNOLOGY REVIEW: In the last few years, two-dimensional crystals have emerged as some of the most exciting new materials to play with. Consequently, materials scientists have been falling over themselves to discover the extraordinary properties of graphene, boron nitride, molybdenum disulphide, and so on.
A late-comer to this group is black phosphorus, in which phosphorus atoms join together to form a two-dimensional puckered sheet. Last year, researchers built a field-effect transistor out of black phosphorus and showed that it performed remarkably well. This research suggested that black phosphorous could have a bright future in nanoelectronic devices.
But there is a problem. Black phosphorus is difficult to make in large quantities. Today, Damien Hanlon at Trinity College Dublin in Ireland, and a number of pals, say they have solved this problem.
These guys have perfected a way of making large quantities of black phosphorus nanosheets with dimensions that they can control. And they have used this newfound ability to test black phosphorus in a number of new applications, such as a gas sensor, an optical switch, and even to reinforce composite materials to make them stronger.
In bulk form, black phosphorus is made of many layers, like graphite. So one way to separate single sheets is by exfoliation, simply peeling off layers using Scotch tape or other materials. That is a time-consuming task that severely limits potential applications.
So Hanlon and co have been toying with another approach. Their method is to place the black phosphorus lump in a liquid solvent and then bombard it with acoustic waves that shake the material apart.
The result is that the bulk mass separates into a large number of nanosheets that the team filters for size using a centrifuge. That leaves high-quality nanosheets consisting of only a few layers. “Liquid phase exfoliation is a powerful technique to produce nanosheets in very large quantities,” they say.
One potential problem with black phosphorus nanosheets is that they degrade rapidly when in contact with water or oxygen. So one of the advances the team has made is to predict that certain solvents should form a solvation shell around the sheet, which prevents oxygen or other oxidative species from reaching the phosphorus.
Physics arXiv: Liquid exfoliation of solvent-stabilised black phosphorus: applications beyond electronics Damien Hanlon, Claudia Backes, Evie Doherty, Clotilde S. Cucinotta, Nina C. Berner, Conor Boland, Kangho Lee, Peter Lynch, Zahra Gholamvand, Andrew Harvey, Saifeng Zhang, Kangpeng Wang, Glenn Moynihan, Anuj Pokle, Quentin M. Ramasse, Niall McEvoy, Werner J. Blau, Jun Wang, Stefano Sanvito, David D. ORegan, Georg S. Duesberg, Valeria Nicolosi, Jonathan N. Coleman
