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Related papers: Electronic States in Diffused Quantum Wells

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Measurements in clean two-dimensional electron systems confined to wide GaAs quantum wells in which two electric subbands are occupied reveal an unexpected rotation of the orientation of the stripe phase observed at a half-filled Landau…

Mesoscale and Nanoscale Physics · Physics 2014-09-23 Yang Liu , D. Kamburov , M. Shayegan , L. N. Pfeiffer , K. W. West , K. W. Baldwin

Time-resolved optical measurements in (110)-oriented GaAs/AlGaAs quantum wells show a ten-fold increase of the spin-relaxation rate as a function of applied electric field from 20 to 80 kV cm-1 at 170 K and indicate a similar variation at…

Condensed Matter · Physics 2009-11-10 O. Z. Karimov , G. H. John , R. T. Harley , W. H. Lau , M. E. Flatte , M. Henini , R. Airey

The three-dimensional nonlinear dynamics of an electron gas in a semiconductor quantum well is analyzed in terms of a self-consistent fluid formulation and a variational approach. Assuming a time-dependent localized profile for the fluid…

Plasma Physics · Physics 2015-06-05 F. Haas

We report the observation of fractional quantum Hall (FQH) effects in a two-dimensional electron gas (2DEG) confined to an InAs/AlGaSb quantum well, using a dual-gated Hall-bar device allowing for the independent control of the vertical…

Mesoscale and Nanoscale Physics · Physics 2022-02-17 S. Komatsu , H. Irie , T. Akiho , T. Nojima , T. Akazaki , K. Muraki

The Hall-plateau width and the activation energy were measured in the bilayer quantum Hall state at filling factor \nu=2, 1 and 2/3, by changing the total electron density and the density ratio in the two quantum wells. Their behavior are…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 A. Sawada , Z. F. Ezawa , H. Ohno , Y. Horikoshi , Y. Ohno , S. Kishimoto , F. Matsukura , M. Yasumoto , A. Urayama

We demonstrated a method to probe local electronic states and energy relaxation in quantum Hall edge states utilizing quantum point contacts. We evaluated relaxation lengths in two cases; first, with electron tunneling, and second, only…

Mesoscale and Nanoscale Physics · Physics 2014-01-28 Tomohiro Otsuka , Yuuki Sugihara , Jun Yoneda , Takashi Nakajima , Seigo Tarucha

We report the existence of confined massless fermion states in a graphene quantum well (QW) by means of analytical and numerical calculations. These states show an unusual quasi-linear dependence on the momentum parallel to the QW: their…

Materials Science · Physics 2007-05-23 J. Milton Pereira , V. Mlinar , F. M. Peeters , P. Vasilopoulos

A two-dimensional (2D) electron gas formed in a modulation-doped GaAs/AlGaAs single quantum well undergoes a first-order transition when the first excited subband is occupied with electrons, as the Fermi level is tuned into resonance with…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 A. R. Goñi , U. Haboeck , C. Thomsen , K. Eberl , F. A. Reboredo , C. R. Proetto , F. Guinea

We study theoretically phonon-assisted relaxation and tunnelling in a system composed of a quantum dot which is coupled to a quantum well. Within the kp method combined with the L\"owdin elimination, we calculate the electron states. We…

Mesoscale and Nanoscale Physics · Physics 2017-12-11 Adam Mielnik-Pyszczorski , Krzysztof Gawarecki , Paweł Machnikowski

In wide GaAs quantum wells where two electric subbands are occupied we apply a parallel magnetic field or increase the electron density to cause a crossing of the two $N=0$ Landau levels of these subbands and with opposite spins. Near the…

Mesoscale and Nanoscale Physics · Physics 2015-11-04 Yang Liu , S. Hasdemir , J. Shabani , M. Shayegan , L. N. Pfeiffer , K. W. West , K. W. Baldwin

Coulomb exchange interactions of electrons in the nu=3 quantum Hall state are determined from two inter-Landau level spin-flip excitations measured by resonant inelastic light scattering. The two coupled collective excitations are linked to…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 A. B. Van'kov , T. D. Rhone , A. Pinczuk , I. V. Kukushkin , L. N. Pfeiffer , K. W. West

Studies of energy flow in quantum systems complement the information provided by common conductance measurements. The quantum limit of heat flow in one dimensional (1D) ballistic modes was predicted, and experimentally demonstrated, to have…

Mesoscale and Nanoscale Physics · Physics 2021-02-02 Amir Rosenblatt , Sofia Konyzheva , Fabien Lafont , Noam Schiller , Jinhong Park , Kyrylo Snizhko , Moty Heiblum , Yuval Oreg , Vladimir Umansky

We report an experimental study of quantum conductivity corrections in a low mobility, high density two-dimensional electron gas in a AlGaAs/GaAs/AlGaAs quantum well in a wide temperature range (1.5K - 110K). This temperature range covers…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 V. T. Renard , I. V. Gornyi , O. A. Tkachenko , V. A. Tkachenko , Z. D. Kvon , E. B. Olshanetsky , A. I. Toropov , J. -C. Portal

Electronic states of PrCoO$_3$ are studied using x-ray photoemission spectroscopy. Pr 3d$_{5/2}$ core level and valence band (VB) were recorded using Mg K$_\beta$ source. The core level spectrum shows that the 3d$_{5/2}$ level is split into…

Strongly Correlated Electrons · Physics 2009-11-11 S. K. Pandey , Ashwani Kumar , S. M. Chaudhari , A. V. Pimpale

3D kinetic-scale turbulence is studied numerically in the regime where electrons are strongly magnetized (the ratio of plasma species pressure to magnetic pressure is $\beta_e=0.1$ for electrons and $\beta_i=1$ for ions). Such a regime is…

Plasma Physics · Physics 2023-07-05 Cristian Vega , Vadim Roytershteyn , Gian Luca Delzanno , Stanislav Boldyrev

We study theoretically the performance of electrically pumped self-organized quantum dots as a gain material in the mid-IR range at room temperature. We analyze an AlGaAs/InGaAs based structure composed of dots-in-a-well sandwiched between…

Materials Science · Physics 2014-10-27 Stephan Michael , Weng W. Chow , Hans Christian Schneider

Equilibrium properties of electrons in double-heterojunction AlGaAs/GaAs\AlGaAs structures are investigated theoretically, using a full self-consistent numerical method. The transition from single to bilayer electron systems is discussed…

Condensed Matter · Physics 2016-08-31 L. Smrcka , T. Jungwirth

Atomistic electronic structure calculations are performed to study the coherent inter-dot couplings of the electronic states in a single InGaAs quantum dot molecule. The experimentally observed excitonic spectrum [12] is quantitatively…

Mesoscale and Nanoscale Physics · Physics 2013-08-01 Muhammad Usman , Yui-Hong Matthias Tan , Hoon Ryu , Shaikh S. Ahmed , Hubert Krenner , Timothy B. Boykin , Gerhard Klimeck

Diffusive transport of a particle in spatially correlated random energy landscape having exponential density of states has been considered. We exactly calculate the diffusivity in the nondispersive quasi-equilibrium transport regime and…

Disordered Systems and Neural Networks · Physics 2018-02-14 S. V. Novikov

Edge states reflect the key physical properties yet are difficult to probe individually, particularly when several states are present at an edge. We present momentum resolved tunneling spectroscopy between a quantum well and a quantum wire…