STUDY ON COHERENT-ELECTRON-OSCILLATION DEVICES USING COUPLED-QUANTUM-STRUCTURES

利用耦合量子结构研究相干电子振荡器件

基本信息

批准号：
10650058
负责人：
TSUKADA Noriaki
金额：
$ 2.05万
依托单位：
AOMORI UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

项目摘要

IN ORDER TO IMPLEMENT THE NEW OPTO-ELECTRONICS QUANTUM HARDWARES FOR INFORMATION PROCESSING, WE HAVE INVESTIGATED THE COHERENT-DYNAMICS OF THE QUANTUM (ATOM AND ELECTRON) WAVE IN THE SEMICONDUCTOR QUANTUM STRUCTURES AS WELL AS LASER-COOLED ATOMS AND THE BOSE-EINSTEIN CONDENSATES IN THE PRESENCE OF EXTERNAL CONTROL FIELDS SUCH AS LASER FIELD, ELECTRIC FIELD, AND MAGNETIC FIELD.THE MAIN RESULTS OBTAINED ARE AS FOLLOWS :(1) WE HAVE STUDIED THE ROTATIONAL MODE OF THE ELECTRONS IN THREE-COUPLED QUANTUM DOTS, WHICH ARE LOCATED AT THE APEXES OF AN EQUILATERAL TRIANGLE, UNDER THE INFLUENCE OF A ROTATIONAL ELECTRIC FIELD.TWO ROTATIONAL MODES ARE PREDICTED ; ONE IS THE COROTATIONAL ONE WHERE THE ELECTRONS ROTATE THE SAME DIRECTION AS THE ROTATING ELECTRIC FIELD AND THE OTHER IS THE COUNTER-ROTATIONAL ONE WHERE THE ELECTRONS ROTATE THE OPPOSITE DIRECTION TO THE ROTATING ELECTRIC FIELD.(2) DYNAMICAL CONTROL OF QUANTUM TUNNELING IN A COUPLED QUANTUM WELL HAS BEEN PREDICTED TO OCCUR WHEN LASER PULSES DRIVE SUBLEVEL TRANSITIONS IN ONE OF THE WELLS.IT WAS SHOWN FOR AN EXAMPLE THAT COMPLETE TUNNELING OSCILLATIONS CAN BE REALIZED, EVEN BETWEEN THE NONRESONANT STATES, BY MEANS OF A TRAIN OF SHORT PULSES WITH APPROPRIATE PULSE INTERVAL AND PULSE AREA.THIS PHENOMENON CAN BE UNDERSTOOD AS THE PHASE MATCHING IN TIME-DOMAIN.(3) WE HAVE INVESTIGATED ATOMIC POPULATION DYNAMICS OF TWO BOSE-EINSTEIN CONDENSATES THAT ARE IN DIFFERENT TRAPS OR IN THE SAME TRAP AND ARE OPTICALLY COUPLED THROUGH A COMMON EXCITED STATE BY RAMAN LASER PULSES.FOR LARGE INTERATOMIC INTERACTIONS, ALMOST ALL OF THE ATOMS THAT ARE INITIALLY IN ONE OF THE TRAPS (OR ONE OF THE INTERNAL STATES) ARE EITHER COMPLETELY TRANSFERRED INTO THE OTHER STATE OR STAY IN THE INITIALLY OCCUPIED STATE AFTER THE LASER PULSES.EVENTUALLY, THE ATOMS (POPULATIONS) ARE NEVER DISTRIBUTED TO BOTH CONDENSATE STATES AT THE SAME TIME.

为了实施用于信息处理的新的光电剂量子硬件，我们研究了半导体量子结构中的量子（原子和电子）波的相干性动力学，以及激光冷却原子以及bose-einstein冷凝物在存在外部控制场上，例如Lasters of Electrifiel Field，Electry Field。在旋转电场的影响下，研究了位于等边三角形的顶端的三耦合量子点中电子的旋转模式。预测两个旋转模式；一种是一个旋律的一个，电子在其中旋转与旋转电场相同的方向，另一个是反旋转的方向，其中电子将相反的方向旋转与旋转电场的相反方向。（2）在耦合量子孔中对量子隧穿的动态控制预计会在激光脉冲中进行示例，以便在一个示例中进行示例，以便在一个示例中进行孔隙式的孔隙，以便在一个示例中进行隧道。 NONRESONANT STATES, BY MEANS OF A TRAIN OF SHORT PULSES WITH APPROPRIATE PULSE INTERVAL AND PULSE AREA.THIS PHENOMENON CAN BE UNDERSTOOD AS THE PHASE MATCHING IN TIME-DOMAIN.(3) WE HAVE INVESTIGATED ATOMIC POPULATION DYNAMICS OF TWO BOSE-EINSTEIN CONDENSATES THAT ARE IN DIFFERENT TRAPS OR IN THE SAME TRAP AND ARE OPTICALLY COUPLED THROUGH A COMMON EXCITED STATE BY RAMAN LASER PULSES.FOR LARGE INTERATOMIC INTERACTIONS, ALMOST ALL OF THE最初位于其中一个陷阱（或一个内部状态）中的原子要么完全转移到另一个状态，要么在激光脉冲之后留在最初占据的状态。最终，原子（种群）永远不会同时分配给两个冷凝水状态。