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quantum tunneling 【物理學】量子隧道貫穿〔指電子穿透勢壘的現象〕。

quantum tunnelling

It is the main purpose of this paper to calculate the energy splitting of ground state and excited states induced by thermally assisted quantum tunneling . first , a brief introduction is given for the theoretical and experimental studies on the magnetic macroscopic quantum effects . then , spin tunneling in a uniaxial ferromagnetic particle in transverse magnetic field is converted to a pseudoparticle moving in effective double - well potential with the help of the effective potential description of quantum spin systems developed by ulyanov and zaslavskii . finally using the periodic instanton method we evaluate the transition amplitude , energy shift and prefactor of wkb exponential and the energy splitting of ground state and the tunneling rate for excited states induced by thermally assisted quantum tunneling are obtained 文章首先對磁性宏觀量子效應的理論和實驗方面作了簡單介紹,然后借助于ulyanov和zaslavskii發展的一種等效勢描述方法,把外磁場沿難磁化軸方向時的自旋隧穿約化成在等效雙勢阱中運動的粒子,利用瞬子方法給出基態能級劈裂,最后利用周期瞬子方法分別計算了隧穿幅、能級移動以及wkb前因子,從而給出由于熱助量子隧穿引起的激發態的隧穿率。

For the transition induced by the asymmetric perturbations is double - direction , the particle number in the core state is always less half of the total particle number . so , from the point of view of average over time , it is a coexisting state of rotating and without rotating that is formed . this state which is in the josephson tunneling regime of the macroscopic quantum tunneling is a quantum self - trapping state 由于不對稱的微擾引起的躍遷是雙向的,使得核心態上的粒子數總是少于總粒子數的一半,因此從時間平均的角度看,形成的是旋轉的和不旋轉的態共存的狀態,而且處于宏觀量子隧穿的約瑟夫森隧穿區域中,是量子自束縛狀態。

The nanometer particles are metastable materials that lie between macroscopical materials and atoms or molecules with the characteristics of little size effect , quantum measurement effect , surface effect and macroscopical quantum tunnel effect , etc . , thus demonstrating some special properties 納米粒子是介于宏觀物質與微觀原子或分子之間的過渡亞穩態物質,具有小尺寸效應、量子尺寸效應、表面效應與宏觀量子隧道效應等,從而表現出一些特殊的性質。

Moreover , we obtain the energy band structure , and the band width of the low - lying energy spectrum of the becs due to the quantum tunneling between degenerate ground states . thus we are able to investigate the coherent properties of the bose - josephson oscillations 此外,我們獲得了由于量子隧穿導致的簡并基態能級劈裂,計算了低能能譜的帶寬,在此基礎上討論了玻色?約瑟夫森振蕩的相干特性。

In this article , four basic properties of nanometer particle are summarized : quantum size effect , surface effect , volume effect , macroscopical quantum tunnel effect , and several ways of preparation and evaluation of nanometer particle are introduced 摘要綜述了納米微粒的四個基本特性:量子尺寸效應、表面效應、體積效應及宏觀量子隧道效應,并介紹了納米微粒的制備方法及對納米微粒評估的方法。

In this chapter , we described some basic properties of nanoparticle , such as quantum - size effect , surface effect , small - size effect , macro - quantum tunnel effect and so on 第一部分:綜述第一章;納米微粒的特性與應用本章主要介紹了納米材料的一些基本特性。例如:量子尺寸效應、表面效應、小尺寸效應、宏觀量子尺寸效應等。

Current flows through the device by the process of quantum tunneling : a small number of electrons manage to jump through the barrier even though they are forbidden to be in the insulator 電子在元件中利用量子穿隧效應流動,少量的電子可穿過絕緣層的障礙到達另一邊。

Starting with the quantum age in 2018 , earth scientists begin experimenting with “ quantum tunneling , “ which will transport living matter great distances 故事開始于2018年的量子時代,地球的科學家開始試驗量子通道,一項技術可以將活質傳送到很遠很遠的敵方。

By analysis and comparison of the results , we draw the conclusion as follows : firstly , the quantum tunneling effect is quite pronounced 通過分析和比較計算結果,我們得到如下結論。第一,體系的能量-反應幾率變化曲線說明量子隧道效應顯著。

But there may be no practical way to make these insulating layers much thinner , because current flow by quantum tunneling makes them progressively worse insulators 但不能讓絕緣層更薄了,因為量子穿隧電流會降低絕緣效果。

Investigation on macroscopic quantum tunneling phenomena under the role of the rotating perturbations is made in the other part of the dissertation 論文的另一部分工作討論有旋轉的微擾作用下的bec系統的宏觀量子隧穿現象。

Thermally assisted quantum tunneling in a uniaxial ferromagnetic particle in transverse magnetic field 單軸鐵磁顆粒激發態的熱助量子隧穿

Quantum tunneling and macroscopic quantum effects in molecular magnets 分子磁體中的量子隧穿及宏觀量子效應

Quantum tunneling of bose - einstein condensates in optical lattices 愛因斯坦凝聚體在光勢阱中的量子隧穿

The hawking radiation of colored black hole as quantum tunneling 通過量子隧穿研究帶色荷黑洞的霍金輻射

Quantum tunnelling time of cold atom passing through a laser beam 冷原子穿越激光束的量子隧穿時間

A quantum tunnel transport takes . 26 seconds 通過量子通道傳送只花費了26秒就到達了。