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Indian origin scientist creates 1st single molecule device

Indian origin scientist creates 1st single molecule device

MUMBAI: Columbia Engineering researchers under the direction of Venkataraman, created a single-molecule diode which performs 50 times better than all prior designs.
Constructing a device where the active element is only a single molecule, has long been a tantalising dream in nanoscience.
“Our new device represents the ultimate in functional miniaturisation that can be achieved for an electronic…

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Northwestern University’s Professor Barnor Hesse’s withdrawal from the Last Lecture as a result of the disrespectful biography nomination written for him. Professor Hesse has asked the organizers to “inform the students voting for ‘last lecture’ not only of my withdrawing my name from nomination, but my reasons for this,” and I’m doubting that they will.


Sent to Jason Hanson, Daniel Linzer, Mark Ratner, and Martha Biondi.

“Dear Jason,

It is with deep regret that I am writing to ask you to withdraw my name from the vote of those nominated to give the 'last lecture’ to the class of 2015. I understand Friday is the last day to vote and would like those who may have voted for me to be given an opportunity to vote for another candidate.

I should like to explain my reasons.

Throughout Wednesday I received various emails from undergraduate students concerned and disgusted with the writing and framing of my biography made available to all the students in the vote. I have now read this biography as well as those of the three other professors nominated. I have to say, it’s quite striking that while each of the other professors is described in relation to their teaching and relationship with students, in short their pedagogy and professionalism, my biography does not include these references and reduces me to a figure of amusement or curiosity. I was described as 'knowing how to put up a fight’, having a 'comical nature’ and 'utterly entertaining’. No reference was made to any of the subjects I teach in African American studies, nor indeed to the various collaborations and projects I have undertaken with undergraduate students over the years, not least of which was recently organizing a 'BlackLivesMatter Teach-in’ in February which had one of the largest student gatherings I have ever seen at NU.

I actually find the description attributed to me and circulated widely to students, demeaning and insulting. There is absolutely no way I can accept being nominated on such disreputable terms.

There is however, another dimension to this, which is not simply personal but speaks to how the University handles questions of diversity. It should not have escaped your attention that I am a black professor who teaches in African American studies. Ironically the terms in which I was described resemble long-standing racist tropes within US (white) culture that associate black people with entertainment value rather than intellectual value, indeed figures of fun rather than seriousness. The contrast in the descriptions attributed to me when compared to the three white female professors also nominated, could not have been starker. Each was depicted in pedagogical and professional terms. Leaving me as it were, the joker in the pack.

I do believe for the class of 2015 this represents a teaching moment. Two of the most popular undergraduate courses I teach at NU are 'Racism in Western Modernity’ and 'Unsettling Whiteness’. These are hardly laughing matters. Among other things they are courses where students are encouraged to develop analyses that expose and critique the kinds of racist tropes I have just been describing. Consequently, it was hardly surprising when some of my current and former students brought to my attention a Facebook page, that had started to discuss the racially demeaning problems associated with the biography attributed to me. The following are some of the more notable criticisms I read in this Facebook discussion on Wednesday:

-'so he’s a professor who shucks and jives for his students?’
-'vicious sarcasm’
-'wow did someone not listen in his class or something’
-'been using the term 'zoo-ified’ lately and I think that’s applicable here’
-'This is all kinds of problematic to me’
-'If he gives the last lecture he could easily speak for an hour on how f’d up his biography is’

These are comments from students who have actually taken my classes. They like I wonder just what kind of message such a racially tendentious biography is sending out to the class of 2015. It also undermines the seriousness and integrity of the Department of African American Studies.

I have no idea whether you will either see or agree with the points I am making, but it is important to me to register my disquiet in the strongest terms. I would summarize the 'teaching moment’ implications of this unseemly debacle in the following way:

1. That this could happen suggests there is no understanding in place of what it means to nurture a mutually shared culture of diversity among students. Not only was the biography for me allowed to be formulated in racially problematic terms by the originating writer, but there was no secondary oversight there to identify how racially offensive it was.

2. It raises the question of what efforts are being made to involve and take seriously the perspectives of students of color in these kinds of process. One of the students that brought the biography to my attention wrote in her email:

"I got an email a few weeks ago where I could submit names of professors that I thought should speak. I was going to submit your name but since I didn’t know what the Last Lecture was, and I figured that the premise of this lecture would not be conducive to the kind of lectures you normally give, I didn’t”

This suggests to me that students of color may be disenfranchised from the whole process of nominations before it even begins, with all the cynicism that entails.

3. The absence of any kind of multicultural literacy on the part of the organizers of this nomination process is truly shocking. Not only does it raise questions about whether there is a serious commitment to diversity here, it actually questions what is being comprehended as a commitment to diversity.

Finally, I ask that you inform the students voting for 'last lecture’ not only of my withdrawing my name from nomination, but my reasons for this. To that end you may circulate this email. I will be circulating this email to the students who wrote to me expressing their concerns.

Best wishes

Barnor"

Single Molecule Diode Paves Way for Microscopic Electronics

Researchers at Columbia and Berkeley have successfully created an effective single molecule diode, a development that could lead to the creation of nano-scale electronic devices. The concept of a single molecule diode was first proposed in 1974 By Mark Ratner and Arieh Aviram, and has until now been a tantalizingly unachievable goal in nanotechnology. Now that a one-molecule diode has been developed, the world may be closer to seeing an entire electronic device contained in one molecule.

WHAT IS A SINGLE MOLECULE DIODE?

A diode basically acts as a gate for the flow of electricity. It only allows electricity to travel through it in one direction. Diodes are a crucial part of the circuits that power the electronic devices we use every day, including the microchips that make computers work. The single molecule diode is exciting because it will allow for a new phase in the miniaturization of electronics.

BETTER THAN BEFORE

Although single molecule diodes have been created in the past, this new molecule outperforms previous attempts by far. The older single molecule diodes were simply molecules designed to have an asymmetrical structure. While the asymmetrical structure did give these molecules some of the properties of diodes, it was not enough to achieve completely unidirectional travel of current.

The new single molecule diode is more than 50 times more effective than its predecessors at making electricity flow only in one direction. It also conducts much more power: 0.1 microamps. The new diode achieves these remarkable results through simple means. Instead of focusing on making the molecule itself asymmetrical, the researchers introduced asymmetry into its environment. Since this single molecule diode is so easily constructed, it will be relatively simple to incorporate into current nano-scale devices.

WHAT’S NEXT?

Diodes are not the only electronic components that might be made out of a single molecule. Since Aviram and Ratner’s 1974 paper, scientists have been experimenting with turning molecules into electrical switches, transistors, and more. The hope is that eventually entire circuits will be built out of single-molecule components. The team of researchers that created the new diode will now focus on trying to understand more clearly the mechanics behind why their new device works.

The idea of creating a single-molecule diode was suggested by Arieh Aviram and Mark Ratner who theorized in 1974 that a molecule could act as a rectifier, a one-way conductor of electric current. Since then the researchers have been exploring the charge-transport properties of molecules.

New Technique To Develop Single-Molecule Diode

William Robinson writes: Under the direction of Latha Venkataraman, associate professor of applied physics at Columbia Engineering, researchers have designed a new technique to create a single-molecule diode, that has rectification ratio as high as 250, and ‘ON’ current as high as 0.1 microamps. The idea of creating a single-molecule diode was suggested by Arieh Aviram and Mark Ratner who theorized in 1974, which has been the 'holy grail’ of molecular electronics ever since its inception to achieve further miniaturization, because single molecule represent the limit of miniaturization.

Read more of this story at Slashdot.



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New Technique To Develop Single-Molecule Diode

William Robinson writes: Under the direction of Latha Venkataraman, associate professor of applied physics at Columbia Engineering, researchers have designed a new technique to create a single-molecule diode, that has rectification ratio as high as 250, and ‘ON’ current as high as 0.1 microamps. The idea of creating a single-molecule diode was suggested by Arieh Aviram and Mark Ratner who theorized in 1974, which has been the 'holy grail’ of molecular electronics ever since its inception to achieve further miniaturization, because single molecule represent the limit of miniaturization.

Read more of this story at Slashdot.


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New Technique To Develop Single-Molecule Diode

William Robinson writes: Under the direction of Latha Venkataraman, associate professor of applied physics at Columbia Engineering, researchers have designed a new technique to create a single-molecule diode, that has rectification ratio as high as 250, and ‘ON’ current as high as 0.1 microamps. The idea of creating a single-molecule diode was suggested by Arieh Aviram and Mark Ratner who theorized in 1974, which has been the 'holy grail’ of molecular electronics ever since its inception to achieve further miniaturization, because single molecule represent the limit of miniaturization.

Read more of this story at Slashdot.



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