356 citations · 1.1k across the 44 of their papers we have counts for
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Mesoscopic System: Semiclassical vs Quantum
Kanchan Meena, Prosenjit Singha Deo, A. M. Jayannavar
We explain a hierarchy of Friedel sum rule like formulas that help us understand response of mesoscopic systems to applied electric and magnetic fields. The formulas can be derived…
A Mechanism to Attract Electrons
Kanchan Meena, P. Singha Deo
In a startling discovery it has been recently found that certain density of states (DOS) can become negative in mesoscopic systems wherein electrons can travel back in time. We giv…
Negative partial density of states in mesoscopic systems
Urbashi Satpathi, P. Singha Deo
Since the experimental observation of quantum mechanical scattering phase shift in mesoscopic systems, several aspects of it has not yet been understood. The experimental observati…
Current carried by evanescent modes and possible device application
Sreemoyee Mukherjee, P. Singha Deo, A. M. Jayannavar
Quantum tunneling of an electron through a classically forbidden regime has no classical analogue and several aspects of it are still not well understood. In this work we analyze e…
Charge and spin density waves: Quasi one dimension to two dimension
Urbashi Satpathi, Sumit Ghosh, A. K. Ray +1
Possibility of electronic charge and spin separation leading to charge density wave and spin density wave is well established in one dimensional systems in presence and absence of…
Stable switch action based on quantum interference effect
Sreemoyee Mukherjee, Ashutosh Yadav, P. Singha Deo
Although devices working on quantum principles can revolutionize the electronic industry, they have not been achieved yet as it is difficult to control their stability. We show tha…
Injectance and a paradox
Urbashi Satpathi, P. Singha Deo
Quantum mechanics manifests in experimental observations in several ways. Hauge et al. (1987) and Leavens et al. (1989) had pointed out that interference effects dominate a physica…
Quantum capacitance: a microscopic derivation
Sreemoyee Mukherjee, M. Manninen, P. Singha Deo
We start from microscopic approach to many body physics and show the analytical steps and approximations required to arrive at the concept of quantum capacitance. These approximati…
S-Matrix Formulation of Mesoscopic Systems and Evanescent Modes
Sheelan Sengupta Chowdhury, P. Singha Deo, A. M. Jayannavar +1
The Landauer-Butikker formalism is an important formalism to study mesoscopic systems. Its validity for linear transport is well established theoretically as well as experimentally…
Non-Ergodic Mesoscopic Systems
P. Singha Deo
Suppose there is a mesoscopic system connected to single channel leads. If the system is non-chaotic or non-ergodic then the thermodynamic and transport properties do not depend on…
Soliton like wave packets in quantum wires
P. Singha Deo
At a Fano resonance in a quantum wire there is strong quantum mechanical back-scattering. When identical wave packets are incident along all possible modes of incidence, each wave…
Charge fluctuations in coupled systems: ring coupled to a wire or ring
P. Singha Deo, P. Koskinen, M. Manninen
Coupled systems in mesoscopic regime are of interest as charge fluctuation between the sub-systems will depend on electron-electron interactions and will play a dominant role in de…
Importance of individual scattering matrix elements at Fano resonances
P. Singha Deo
Single particle resonances in quantum wires are generally Fano resonances. In case of Fano resonances, the scattering phase shift in some channels show sharp phase drops and that i…
Quantum current magnification in a multi-channel mesoscopic ring
Swarnali Bandopadhyay, P. Singha Deo, A. M. Jayannavar
We have studied the current magnification effect in a multi-channel open mesoscopic ring. We show that the current magnification effect is robust even in the presence of several pr…
Energy spectrum, persistent current and electron localization in quantum rings
M. Manninen, P. Koskinen, M. Koskinen +3
Energy spectra of quasi-one-dimensional quantum rings with a few electrons are studied using several different theoretical methods. Discrete Hubbard models and continuum models are…
Quantum rings for beginners: Energy spectra and persistent currents
S. Viefers, P. Koskinen, P. Singha Deo +1
Theoretical approaches to one-dimensional and quasi-one-dimensional quantum rings with a few electrons are reviewed. Discrete Hubbard-type models and continuum models are shown to…
Larmor precession time, Wigner delay time and the local density of states in a quantum wire
P. Singha Deo
Buttiker-Thomas-Pretre (BTP) [Z. Phys B {\bf 94}, 133 (1994)] proposed that the concepts behind the Larmor clock tell us that it is possible to define exactly the local density of…
Friedel Sum Rule for single channel quantum wire
Swarnali Bandopadhyay, P. Singha Deo
Elastic scattering in a quantum wire has several novel features not seen in 1D, 2D or 3D. In this work we consider a single channel quantum wire as its application is inevitable in…
Fractional Periodicity of Persistent Currents: A Signature of Broken Internal Symmetry
P. Singha Deo, P. Koskinen, M. Koskinen +1
We show from the symmetries of the many body Hamiltonian, cast into the form of the Heisenberg (spin) Hamiltonian, that the fractional periodicities of persistent currents are due…
Scattering phase shifts in quasi-one-dimension
P. Singha Deo, Swarnali Bandopadhyay, Sourin Das
Scattering of an electron in quasi-one dimensional quantum wires have many unusual features, not found in one, two or three dimensions. In this work we analyze the scattering phase…
Current-spin-density functional study of persistent currents in quantum rings
S. Viefers, P. Singha Deo, S. M. Reimann +2
We present a numerical study of persistent currents in quantum rings using current spin density functional theory (CSDFT). This formalism allows for a systematic study of the joint…
Violation of general Friedel sum rule in mesoscopic systems
P. Singha Deo
In the wake of a new kind of phase generally occurring in mesoscopic transport phenomena, we discuss the validity of Friedel sum rule in the presence of this phase. We find that th…
Vortex Matter in Mesoscopic Superconducting Disks and Rings
F. M. Peeters, V. A. Schweigert, B. J. Baelus +1
Phase transitions between different (i.e. giant and multi-vortex) superconducting states and between the superconducting-normal state of mesoscopic disks and rings are studied in t…
Features of level broadening in a ring-stub system
P. Singha Deo, M. V. Moskalets
When a one dimensional (1D) ring-stub system is coupled to an electron reservoir, the states acquire a width (or broadening characterized by poles in the complex energy plane) due…