Job announcements relevant to people interested in electronic structure calculations…
Due to the large number of posts recently, there is currently a delay of several weeks between posts being submitted and the corresponding emails being distributed to all users. Please bear with us while we try to improve this. In the meantime – and until this notice is removed – it would assist us considerably if you could submit only important and/or urgent posts and thus help to reduce the size of the mail queue. Under no circumstances should you resend posts multiple times when you find the emails are not distributed immediately.
In light of the Russian military offensive in Ukraine, we request that announcements relating to events, jobs and other activities associated with institutions supported by the Russian and Belarusian states are not posted to the Psi-k forum.
PhD position at CEA/Institut Néel in quantum tr ... (No replies)
Back to Job listings...
A PhD position (3 years from September 1, 2016 or as soon as possible thereafter) is available at CEA Leti/Institut Néel, Grenoble (France) on "Quantum transport in OxRAM nanoelectronic devices by ab initio non-equilibrium Green function (NEGF) theory"
Resistive non-volatile random-access memories based on oxides (OxRAM) have been proposed for their performances as a replacement technology in flash memories and are actually developped by a number of companies [1]. Their operation is based on the reversible modifcation of intrinsic caracteristics of the oxide allowing to change its electrical resistivity. Nevertheless, the microscopic mechanisms underlying their working principle are not yet understood. This has the effect to hold back technological improvements.
The object of this thesis is the theoretical study of hafnium (HfO2) and tantalum oxides (Ta2O5) OxRAM memories by ab initio non-equilibrium Green function (NEGF) theory [2, 3]. The candidate will rst perform calculations of both the atomic and the electronic structure of these nanoelectronic devices in their operating conditions. He will rely on previous theoretical works [4, 5] and in situ physical characterizations of real devices. The final ambitious objective is to be able to calculate the I/V characteristics such as to achieve full comprehension of the device operating mechanisms. One possible extension is to evaluate out of equilibrium forces in order to investigate the driving forces leading to ions motion [6].
The candidate is required to have solid bases in theoretical physics and condensed matter and must demonstrate experience in computer programming. At the end the PhD will have acquired knowledge of density-functional and Green function theories for non-equilibrium quantum transport, as well as software implementing them (any prior knowledge on any of them will be considered a favouring factor). Applications including a brief cover letter, CV and master marks have to be sent to the supervisors (see below for contact information). The deadline for application is June 5, 2016.
CEA supervisors
Dr. Benoît Sklénard
Tel: +33(0)4 38 78 65 32
E-mail: [email protected]
Dr. Francois Triozon
Tel: +33 (0)4 38 78 21 86
E-mail: [email protected]
Academic supervisor
Dr. Valerio Olevano
Tel: +33 (0)4 56 38 71 44
E-mail: [email protected]
References:
[1] D. Ielmini, R. Waser, Resistive Switching: From Fundamentals of Nanoionic Redox Processes to Memristive Device Applications, Wiley-Vch, 2016
[2] G. Stefanucci and R. van Leeuwen, Nonequilibrium Many-Body Theory of Quantum Systems, A Modern Introduction, Cambridge, 2013
[3] J. Rammer and H. Smith, Quantum field-theoretical methods in transport theory of metals, Rev. Mod. Phys. 58, 323, 1986
[4] K.-H. Xue, P. Blaise, L. R. C. Fonseca, Y. Nishi, Prediction of semimetallic tetragonal Hf2O3 and Zr2O3 from first principles, Phys. Rev. Lett. 110, 065502, 2013
[5] B. Traore , P. Blaise, E. Vianello, H. Grampeix, S. Jeannot, L. Perniola, B. De Salvo and Y. Nishi, On the Origin of Low-Resistance State Retention Failure in HfO2-Based RRAM and Impact of Doping/Alloying, IEEE Transactions on Electron Devices 62, 4029, 2015
[6] J.-T. Lu, M. Brandbyge and P. Hedegard, Blowing the Fuse: Berry's Phase and Runaway Vibrations in Molecular Conductors, Nano Lett. 10, 1657-1663, 2010