Persistent Current in Metallic Rings and Cylinders

Abstract

PrefaceWe explore the behavior of persistent current and low-field magnetic response in mesoscopic one-channel rings and multi-channel cylinders within the tight-binding framework.We show that the characteristic properties of persistent current strongly depend on total number of electrons N e , chemical potential µ, randomness and total number of channels.The study of low-field magnetic response reveals that only for one-channel rings with fixed N e , sign of the low-field currents can be predicted exactly, even in the presence of disorder. On the other hand, for multi-channel cylinders, sign of the low-field currents cannot be mentioned exactly, even in the perfect systems with fixed N e as it significantly depends on the choices of N e , µ, number of channels, disordered configurations, etc.

Distribution of persistent currents in a multi-arm mesoscopic ring

“…These currents are periodic in φ exhibiting φ 0 fluxquantum periodicity. The presented current-flux characteristics for this single-channel ring exactly match with the previous theoretical studies where persistent currents have been calculated by other approaches [1][2][3][4][5][6][7][8][9][10].…”

“…The appearance of discrete energy levels and large phase coherence length allow a non-decaying current in presence of an AB flux φ. Following the pioneering work of Büttiker et al [1], various efforts have been made to explore the basic mechanisms of persistent current in mesoscopic rings and cylinders [2][3][4][5][6][7][8][9][10]. Later, the existence of non-decaying current in these systems has also been verified through some nice experiments [11][12][13][14].…”

Quantum transport in an array of mesoscopic rings: Effect of interface geometry

“…At thermodynamic equilibrium, electrons in a mesoscopic ring, threaded by magnetic flux φ, can support non-decaying current even at non-zero temperature. This is the well-known phenomenon and the socalled persistent current [10,11,12,13,14,15,16] in normal metal ring. On the other hand, current trend of the miniaturization of electronic devices has resulted in intensive interest in characterization of these types of nanostructures.…”

Magnetic response of non-interacting and interacting electrons in a Möbius strip

“…This is the so-called persistent current, an obvious demonstration of AB effect, and was first proposed by Büttiker et al 8 during early 80's. Following this pioneering work, substantial theoretical and experimental works [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] have been done along this line to understand different aspects of persistent current and other related issues in isolated conducting loops. In particular, the physics of quantum rings has always been the subject of intense research due to its potential applications in designing electronic, spintronic, optoelectronic and information processing devices.…”

“…These features are not discussed here as they are beyond the scope of our present work, and hopefully we will reproduce them in our forthcoming work. Now, the works involving flux-driven persistent current in isolated systems are mostly confined to simple loop geometries like single-channel rings, multi-channel cylinders, graphene rings, nanotubes, array of rings to name a few [9][10][11][12][13][14][15][16][17][18][19][20] . Whereas, very few works are available where twisted geometries have been taken into account.…”