English
Related papers

Related papers: Temperature stability of intersubband transitions …

200 papers

The magnetic sensitivity of Hall-effect sensors made of InAlN/GaN and AlGaN/GaN heterostructures was measured between room temperature and 576{\deg}C. Both devices showed decreasing voltage-scaled magnetic sensitivity at high temperature,…

We explore the midinfrared absorption of strain-compensated p-Si0.2Ge0.8/Si quantum wells for various well thicknesses and temperatures. Owing to the large band offset due to the large bi-axial strain contrast between the wells and…

Other Condensed Matter · Physics 2009-11-11 S. Tsujino , A. Borak , C. Falub , T. Fromherz , L. Diehl , H. Sigg , D. Gruetzmacher

Quantum confinement profoundly affects the properties and interactions of electrons, holes, and excitons in nanomaterials. We apply first-principles calculations to study the effects of extreme quantum confinement on the electronic,…

Materials Science · Physics 2019-10-07 Dylan Bayerl , Emmanouil Kioupakis

We report on the exciton propagation in polar (Al,Ga)N/GaN quantum wells over several micrometers and up to room temperature. The key ingredient to achieve this result is the crystalline quality of GaN quantum wells (QWs) grown on GaN…

Mesoscale and Nanoscale Physics · Physics 2016-07-27 F. Fedichkin , T. Guillet , P. Valvin , B. Jouault , C. Brimont , T. Bretagnon , L. Lahourcade , N. Grandjean , P. Lefebvre , M. Vladimirova

This work studies the effect of temperature on the binding energy of a shallow hydrogenic impurity located on the axis of a cylindrical semiconductor GaAs Al_x Ga_{1-x} As quantum well wire. The results show that the binding energy at a low…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 T G Emam

We present measurements of the resonant microwave absorption by the Rydberg energy levels of surface state electrons on the surface of superfluid liquid helium, in the frequency range 165 - 220 GHz. The resonant frequency was strongly…

Mesoscale and Nanoscale Physics · Physics 2017-12-27 E. Collin , W. Bailey , P. Fozooni , P. G. Frayne , P. Glasson , K. Harrabi , M. J. Lea

We determine the diffusion length of excess carriers in GaN by spatially resolved cathodoluminescence spectroscopy utilizing a single quantum well as carrier collector or carrier sink. Monochromatic intensity profiles across the quantum…

We have investigated the intersubband transitions of surface state electrons (SSE) on liquid $^3$He induced by microwave radiation at temperatures from 1.1 K down to 0.01 K. Above 0.4 K, the transition linewidth is proportional to the…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Hanako Isshiki , Denis Konstantinov , Hikota Akimoto , Keiya Shirahama , Kimitoshi Kono

GaN nanowire ensembles with axial InGaN multi-quantum wells (MQWs) were grown by molecular beam epitaxy. In a series of samples, we varied the In content in the MQWs from almost zero to about 20%. Within the nanowire ensemble, the MQWs…

We study the adsorption behavior of Ga on (0001) GaN surfaces combining experimental specular reflection high-energy electron diffraction with theoretical investigations in the framework of a kinetic model for adsorption and ab initio…

Materials Science · Physics 2009-11-10 C. Adelmann , J. Brault , G. Mula , B. Daudin , L. Lymperakis , J. Neugebauer

We study the exciton gas-liquid transition in GaAs/AlGaAs coupled quantum wells. Below a critical temperature, Tc=4.8K, and above a threshold laser power density the system undergoes a phase transition into a liquid state. We determine the…

Mesoscale and Nanoscale Physics · Physics 2018-02-14 Subhradeep Misra , Michael Stern , Arjun Joshua , Vladimir Umansky , Israel Bar-Joseph

Steady-state access to intraband transitions in colloidal quantum dots (CQDs), via heavy doping, allows exploiting the electromagnetic spectrum at energies below the band gap. CQD intraband optoelectronics opens up a new path to cheap mid-…

Mesoscale and Nanoscale Physics · Physics 2020-01-14 Iñigo Ramiro , Biswajit Kundu , Mariona Dalmases , Onur Özdemir , María Pedrosa , Gerasimos Konstantatos

The effect of outdiffusion of Mn interstitials from (Ga,Mn)As epitaxial layers, caused by post-growth low-temperature annealing, on their electronic- and band-structure properties has been investigated by modulation photoreflectance (PR)…

Materials Science · Physics 2015-06-16 O. Yastrubchak , T. Andrearczyk , J. Z. Domagala , J. Sadowski , L. Gluba , J. Zuk , T Wosinski

We report experimental studies of conductance and magnetoconductance of GaAs/AlGaAs quantum well structures where both wells and barriers are doped by acceptor impurity Be. Temperature dependence of conductance demonstrate a non-monotonic…

Disordered Systems and Neural Networks · Physics 2015-12-16 N. V. Agrinskaya , V. A. Berezovets , V. I. Kozub

The temperature and magnetic field dependences of the conductivity of the heterostructures with asymmetric In$_x$Ga$_{1-x}$As quantum well are studied. It is shown that the metallic-like temperature dependence of the conductivity observed…

Disordered Systems and Neural Networks · Physics 2008-12-02 G. M. Minkov , A. V. Germanenko , A. A. Sherstobitov , B. N. Zvonkov

AlN thin films have been grown on Si (100) substrates by reactive ion beam sputter deposition (IBSD) at different substrate temperatures varying from room temperature (RT) to 500oC. Substrate temperature induced microstructural transition…

Materials Science · Physics 2016-02-23 Neha Sharma , Shilpam Sharma , K. Prabakar , S. Amirthapandian , S. Ilango , S. Dash , A. K. Tyagi

The growth-diection quantization of confined electron gas in a GaAs/AlGaAs based quantum well structure is obtained in the Kohn-Sham iterative computational scheme. The longitudinal conductance at low temperatures, in the presence of…

Mesoscale and Nanoscale Physics · Physics 2009-01-14 Partha Goswami , Garima Puneyani , Avinashi Kapoor

GaN/AlxGa1-xN quantum wells were grown by molecular beam epitaxy on high quality bulk (0001) GaN substrates. The quantum well thickness was set in the 6-8 nm range to favor the photoluminescence emission of indirect excitons. Indeed, such…

Absorption spectroscopy is traditionally used to determine the average gas temperature and species concentration along the laser line-of-sight by measuring the magnitude of two or more absorption transitions with different temperature…

Applied Physics · Physics 2020-12-01 Nathan A Malarich , Gregory B Rieker

Experimental studies of magnetoresistance in high-mobility wide quantum wells reveal oscillations which appear with an increase in temperature to 10 K and whose period is close to that of Shubnikov-de Haas oscillations. The observed…

Mesoscale and Nanoscale Physics · Physics 2010-11-01 S. Wiedmann , G. M. Gusev , O. E. Raichev , A. K. Bakarov , J. C. Portal