Peierls Gap in a Mesoscopic Ring Threaded by a Magnetic Flux

1997 ◽  
Vol 78 (18) ◽  
pp. 3523-3526 ◽  
Author(s):  
J. Yi ◽  
M. Y. Choi ◽  
K. Park ◽  
E.-H. Lee
2011 ◽  
Vol 25 (22) ◽  
pp. 3019-3025
Author(s):  
QING-QIANG XU ◽  
BEN-LING GAO ◽  
SHI-JIE XIONG

We investigate the transport properties of an interacting ring threaded by a magnetic flux and with Rashba spin-orbit coupling, based on a recently developed functional renormalized group technique. In the calculations of the electronic transport processes, the Coloumb On-site interactions are taken into account. For an interacting ring connected to two leads, we find that (i) for ΦAC = 0, the behavior of transmission zero at ΦAB = π is generic for the universal regime; (ii) for certain ΦAC and ΦAB, one can use the mesoscopic ring as spin filter even in the presence of the local interaction in the ring.


1992 ◽  
Vol 45 (7) ◽  
pp. 3499-3506 ◽  
Author(s):  
B. Nathanson ◽  
O. Entin-Wohlman ◽  
B. Mühlschlegel

1998 ◽  
Vol 12 (06) ◽  
pp. 663-672
Author(s):  
Ben-Yuan Gu ◽  
Wei-Dong Sheng ◽  
Jian Wang

The energy spectrum and the persistent currents are calculated for a finite-width mesoscopic annulus with radial potential barrier, threading a magnetic flux through the hole of the ring. Owing to the presence of tunneling barrier, the coupling effect leads to the splitting of each radial energy subband of individual concentrical rings into two one. Thus, total currents and currents carried by single high-lying eigenstate as a function of magnetic flux exhibit complicated patterns. However, periodicity and antisymmetry of current curves in the flux still preserve.


1998 ◽  
Vol 80 (15) ◽  
pp. 3416-3416 ◽  
Author(s):  
B. Nathanson ◽  
O. Entin-Wohlman ◽  
B. Mühlschlegel

1995 ◽  
Vol 09 (20) ◽  
pp. 2719-2734 ◽  
Author(s):  
ALMAS F. SADREEV ◽  
VALERY A. VID’MANOV

Transport properties of mesoscopic rings confined between potential barriers are considered. Also considered is the double barrier structure with barriers fabricated of rings connected by a one-dimensional wire. Such structures we define as Aharonov-Bohm diodes with resonant tunneling (ABDRT) because for zero external magnetic flux their transport properties are quite similar to diodes with resonant tunneling (DRT). However, application of external magnetic flux gives rise to new resonant peaks of transmission determined by the quantization condition of the rings. Positions and widths of these novel flux induced resonant peaks extremely depend on the flux.


2000 ◽  
Vol 179 ◽  
pp. 263-264
Author(s):  
K. Sundara Raman ◽  
K. B. Ramesh ◽  
R. Selvendran ◽  
P. S. M. Aleem ◽  
K. M. Hiremath

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust & Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust & Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.


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