Solid State Physics Laboratory

About: Solid State Physics Laboratory is a facility organization based out in Delhi, India. It is known for research contribution in the topics: Quantum dot & Dielectric. The organization has 1754 authors who have published 2597 publications receiving 50601 citations.

Gating of high-mobility two-dimensional electron gases in GaAs/AlGaAs heterostructures

Abstract: In this work, we investigate high-mobility two-dimensional electron gases in AlxGa1-xAs heterostructures by employing Schottky-gate-dependent measurements of the samples' electron density and mobility. Surprisingly, we found that two different sample configurations can be set in situ with mobilities differing by a factor of more than two in a wide range of densities. This observation is discussed in the context of charge redistributions between the doping layers and is relevant for the design of future gateable high-mobility electron gases.

Electronic transport through a quantum dot network

Abstract: The conductance through a finite quantum dot network is studied as a function of interdot coupling. As the coupling is reduced, the system undergoes a transition from the antidot regime to the tight binding limit, where Coulomb resonances with on average increasing charging energies are observed. Percolation models are used to describe the conduction in the open and closed regime and contributions from different blockaded regions can be identified. A strong negative average magnetoresistance in the Coulomb blockade regime is in good quantitative agreement with theoretical predictions for magnetotunneling between individual quantum dots.

Tunnelling- and barrier-injection transit-time mechanisms of terahertz plasma instability in high-electron mobility transistors

Abstract: We study theoretically the plasma instability in a heterostructure similar to a high-electron mobility transistor. The instability under consideration is associated with the transit-time effects of the electrons injected from the channel into the gate layer due to tunnelling or thermionic emission. The frequencies of the self-excited plasma oscillations, which fall within the terahertz range, are determined by the electron concentration in the channel and its length. We find the instability criteria expressed via the structural parameters and applied voltage.