Electric-field-induced resonant tunneling lifetime in semiconductor multibarrier systems

Abstract

A study on the variation in resonant tunneling lifetime (RTL) with the applied electric field is presented for the GaAs/AlxGa1−xAs periodic multibarrier systems (MBSs). The variation shows a contrasting behavior of lifetime for quasiresonant states situated at the miniband edge and those for well inside the miniband. For fields larger than 500 kV/m, the RTL corresponding to the midband state increases with the increase in electric field, whereas it decreases with the increase in field for the states near the miniband edges. The existence of the characteristic field and the characteristic lifetime that represent the synchronization of carrier velocity associated with all the quasiresonant states is an interesting outcome of the present theoretical investigation in ballistic transport of carriers through a MBS. This synchronization results in the maximum average escape rate through the system. It has also been shown that the characteristic field corresponds to the formation of localized partial Wannier–Stark ladder states in the miniband.

Microscopic Quantum Transport Processes of Out‐of‐Plane Charge Flow in 2D Semiconductors Analyzed by a Fowler–Nordheim Tunneling Probe

“…Considering the energy‐time uncertainty principle Δ E Δ t ∼ ħ /2, we can argue that charge carriers tunneling through the 2D barrier momentarily stay in the tunnel junction for Δ t ∼ ħ /(2Δ E ), which is related to the resonant tunnel lifetime in a semiconductor tunnel junction where Δ E is the half‐width half‐maximum of the transmission coefficient. [ 42 ] During this transitory stay, charges travel by λ = v Δ t , later expressed as λ = ħ /(2 m *Δ E ) 1/2 by combining the de Broglie wave p = m * v = ħ /λ and the uncertainty principle for Δ t ; namely, a lighter effective mass indicates that tunneling charges can transport deeper into the barriers. For the particular case that the thickness of an insulating layer d becomes thinner than λ, the penetration depth λ can naturally be replaced by d .…”

“…Considering the energy-time uncertainty principle ΔEΔt ∼ ħ/2, we can argue that charge carriers tunneling through the 2D barrier momentarily stay in the tunnel junction for Δt ∼ ħ/(2ΔE), which is related to the resonant tunnel lifetime in a semiconductor tunnel junction where ΔE is the half-width half-maximum of the transmission coefficient. [42] During this transitory stay, charges travel by λ = vΔt, later expressed as λ = ħ/(2m*ΔE) 1/2 by combining the de Broglie wave p = m*v = ħ/λ and the uncertainty principle for Δt; namely, a lighter effective mass indicates that tunneling charges can transport deeper into the barriers. For the particular case that the thickness of an insulating layer d becomes thinner than λ, the penetration depth λ can naturally be replaced by d. Following this simple heuristic argument, we www.advelectronicmat.de can make two postulates: i) the bulk effective mass m* defines the critical thickness d c = ħ/(2m*ΔE) 1/2 at which the vertical quantum tunneling exhibits a crossover from bulk to 2D multiband transport, and ii) the "equivalent" charge carrier effective mass in an atomically thin SCTMD insulator reconfigures as m* 2D = ħ 2 /(2ΔEd 2 ).…”

Resonant tunnelling in a Fibonacci bilayer graphene superlattice

“…Due to the chiral nature of these pseudo‐particles, graphene crystallites exhibit a number of exceptional electronic properties 3–11 and deserve special attention for theoretical and experimental studies. Among the various electronic properties, transport phenomena based on resonant tunnelling are now well established and the understanding of different time‐dependent aspects of tunnelling is now almost clear for conventional semiconductor systems 12. However, only little effort has been expended on the study of the resonant behaviour of these chiral particles in graphene systems.…”

Relativistic resonant tunneling lifetime for double barrier system

“…During last two decades or so, the resonant tunneling has become an important facet of condensed matter physics [1,2,3,4,5,6,7,8,9]. In the recent years the investigation of the lifetime of states corresponding to resonant tunneling has drawn considerable attentions [1,2,3,5,6,7,8].…”

“…In the recent years the investigation of the lifetime of states corresponding to resonant tunneling has drawn considerable attentions [1,2,3,5,6,7,8]. While studying the resonant tunneling relativistically, it has been found that the resonant states occur in lower energies as compared to the non-relativistic (NR) ones [10,11].…”