氢原子的量子谐振动理论

给出做量子谐振动的氢原子精确的量子哈密顿量,建立适合氢原子特性的量子算符代数理论,根据创新的氢原子的量子算符代数理论,得到氢原子的能量及氢原子的光谱常数表示。结果表明:氢原子的光谱常数与实验测定值完全符合。     

氢原子的量子力学表征

建立了适合氢原子特性的量子算符代数理论,给出氢原子中电子与原子核绕其质心作圆周运动的旋转角频率及其轨道速度等物理量与时间量子数之间的关系。根据氢原子的量子算符代数理论,得到氢原子的能量及氢原子的光谱常数表示。结果表明,氢原子的光谱常数与实验测定值完全符合。     

微观粒子量子谐振动的量子力学表征

对微观粒子量子谐振动的量子尺寸效应进行表征,给出量子谐振子精确的量子哈密顿量,建立适合量子谐振子特性的量子算符代数理论。根据创新的量子谐振子的量子算符代数理论,得到量子谐振子的能量关系。结果表明:量子谐振子的能量为常量,其值与时间量子数无关,不同时间量子态量子谐振子的能量都相同。     

Kubelka-Munk理论及其在混合矿物 颜料配色中的应用

选取石青、石绿、水晶末3种矿物颜料,通过不同的比例将它们进行混合,并测量各混合颜料的光谱反射率。利用双常数Kubelka-Munk理论计算出3种颜料各自的吸收系数K和散射系数S的值,利用吸收系数和散射系数的加和性,通过计算机配色得到混合颜料理论上的光谱反射率值,并与前面直接测得的光谱反射率对比,计算其色差和均方根。同时,通过纯颜料的K/S值并利用其加和性进行计算机配色,得到单常数K-M理论配色后的K/S值,计算其对应的光谱反射率。再将单常数K-M理论配色后的光谱反射率与实际测量得到的光谱反射率进行对比,计算二者的色差和均方根,最后根据两组色差值和均方根评价单常数和双常数K-M理论在混合矿物颜料配色时的表现。结果表明,双常数K-M理论应用在3种颜料混合的情况时,能得到较为满意的配色结果。     

光孤子对量子态的高速调制

从高速调制的角度,研究了量子光通信系统。提出用孤子调制承载量子态的方案。方案着重从调制量子态的通信信道出发,分别论证了孤子在NLSE光纤和SIT媒介中的传输演变;得出量子压缩态和纠缠态可以在二级传输线(由传统光纤和支持自激励透明孤子的二级媒介组成)中,由孤子的传输演变产生;从而实现孤子对量子态的调制。这种调制方案,利用了光的波粒二重性,融合了量子和孤子的特性,是未来量子光通信的一种发展趋势。     

一种简单的水热法制备油溶性PbSe量子点

本研究采用简单的水热法得到了单一形态学和小尺寸分布的油溶性PbSe量子点。所得到的立方相PbSe量子点颗粒呈现近球形, 且平均颗粒尺寸为4.0 ± 0.5 nm。PbSe量子点在435 nm近紫外区域呈现出较强的和相对较窄的光致发光光谱, 光谱的半高宽值约为80 nm。随着反应时间的延长和反应温度的升高, 发光光谱向低能量区域移动, 谱峰的半高宽也随之变大。在改变前驱体Pb/S摩尔比的条件下, 发光光谱相对强度降低, 光谱也发生向长波长区域移动。另外, 随着反应温度和前驱体Pb/S摩尔比的改变, PbSe量子点颗粒表面的缺陷也增多。在反应过程中, 小颗粒长大成大尺寸颗粒促使PbSe量子点的发光光谱向长波长移动, 这个现象符合奥斯瓦尔德熟化定律。热力学不稳定和颗粒表面低浓度油酸包覆也造成PbSe量子点颗粒表面产生缺陷。     

一种简单的水热法制备油溶性PbSe量子点（英文）

本研究采用简单的水热法得到了单一形态学和小尺寸分布的油溶性Pb Se量子点。所得到的立方相Pb Se量子点颗粒呈现近球形,且平均颗粒尺寸为4.0±0.5 nm。Pb Se量子点在435 nm近紫外区域呈现出较强的和相对较窄的光致发光光谱,光谱的半高宽值约为80 nm。随着反应时间的延长和反应温度的升高,发光光谱向低能量区域移动,谱峰的半高宽也随之变大。在改变前驱体Pb/S摩尔比的条件下,发光光谱相对强度降低,光谱也发生向长波长区域移动。另外,随着反应温度和前驱体Pb/S摩尔比的改变,Pb Se量子点颗粒表面的缺陷也增多。在反应过程中,小颗粒长大成大尺寸颗粒促使Pb Se量子点的发光光谱向长波长移动,这个现象符合奥斯瓦尔德熟化定律。热力学不稳定和颗粒表面低浓度油酸包覆也造成Pb Se量子点颗粒表面产生缺陷。     

微观粒子的量子摄动理论

给出微观粒子量子摄动系统的量子哈密顿量,建立量子摄动系统的量子算符代数理论,得到量子摄动系统的能量表示。结果表明,微观粒子的量子摄动角频率随着时间量子数的增加而减小;作量子摄动的微观粒子的能量也随着时间量子数的增加而减小。     

电镜图像的量子衍生增强算法

在量子信息处理框架下,从像素灰度归一化、像素量子态表示、量子测量、测量结果映射等方面,总结了现有量子衍生图像增强算法的处理流程。以 SARS-CoV-2 新冠病毒电镜图像增强为样本,结合实验分析,改进了量子衍生增强算子的加权方式,提出了灰度变换可调参数优化值的非迭代式确定算子。实验结果表明,量子衍生增强算法综合考虑了电镜图像的全局与局部信息,兼顾了对电镜图像对比度与亮度的调节,图像细节清晰、明暗适宜。     

准二维4×4量子点磁化动力学特性的Monte Carlo模拟

基于Monte Carlo模拟,研究了准二维4×4量子点阵列中交换相互作用常数J、偶极相互作用常数D、磁晶各向异性常数K对自旋组态和相关磁特性的影响。模拟结果表明,量子点阵列和单个量子点表现出完全不同的磁特性,即量子点阵列表现为顺磁性,而单个量子点则为铁磁性;分析不同外磁场下体系自旋组态的变化可以很好地解释模拟结果。     

纳米颗粒的超导转变温度

首次给出一组适合声子特点的共轭复量子数算符,由此建立声子的量子算符代数理论,根据该理论得到声子的量子化能量、纳米颗粒的晶格点阵热容和纳米颗粒的超导转变温度的具体表示。结果表明,声子的量子化能量、纳米颗粒的晶格点阵热容和纳米颗粒的超导转变温度均与声子的量子尺寸、状态量子数及时间量子数有关。     

量子引力场中纳米颗粒的量子理论

首次给出纳米颗粒哈密顿量的明确表示。根据纳米颗粒的量子自旋特性,得到纳米颗粒质量随时间变化的规律。根据纳米颗粒哈密顿量的守恒条件,得到纳米颗粒的量子平动动量、纳米颗粒的量子转动动量、纳米颗粒所受的量子引力及纳米颗粒与纳米颗粒引力中心的量子距离随时间变化的规律。证明纳米颗粒的量子平动动量、纳米颗粒与纳米颗粒引力中心的量子距离、纳米颗粒的量子能量均与颗粒所处的量子状态有关。对于不同量子状态的纳米颗粒,上述物理量的取值不同。本文中创新一组满足对易关系互为共轭的复量子数算符,建立纳米颗粒的量子算符代数理论,得到纳米颗粒能量的量子化表示。     

金属光电效应的量子理论

为研究金属光电效应的量子理论,给出金属中一个电子的总哈密顿量,建立适合电子量子振动特性的算符代数理论,根据量子算符代数理论,得到金属中一个电子的总能量,由光电效应理论得到一个自由光子的静止质量和一个自由光子的能量表示。     

含自旋轨道相互作用的氢原子精确量子论

首次建立超微粒子费密算符理论。利用该理论 ,并结合文献 [1]的工作 ,得到含自旋轨道相互作用的氢原子精确量子论。     

Quantitative excited state spectroscopy of a single InGaAs quantum dot molecule through multi-million-atom electronic structure calculations

Atomistic electronic structure calculations are performed to study the coherent inter-dot couplings of the electronic states in a single InGaAs quantum dot molecule. The experimentally observed excitonic spectrum by Krenner et al (2005) Phys. Rev. Lett. 94 057402 is quantitatively reproduced, and the correct energy states are identified based on a previously validated atomistic tight binding model. The extended devices are represented explicitly in space with 15-million-atom structures. An excited state spectroscopy technique is applied where the externally applied electric field is swept to probe the ladder of the electronic energy levels (electron or hole) of one quantum dot through anti-crossings with the energy levels of the other quantum dot in a two-quantum-dot molecule. This technique can be used to estimate the spatial electron-hole spacing inside the quantum dot molecule as well as to reverse engineer quantum dot geometry parameters such as the quantum dot separation. Crystal-deformation-induced piezoelectric effects have been discussed in the literature as minor perturbations lifting degeneracies of the electron excited (P and D) states, thus affecting polarization alignment of wavefunction lobes for III-V heterostructures such as single InAs/GaAs quantum dots. In contrast, this work demonstrates the crucial importance of piezoelectricity to resolve the symmetries and energies of the excited states through matching the experimentally measured spectrum in an InGaAs quantum dot molecule under the influence of an electric field. Both linear and quadratic piezoelectric effects are studied for the first time for a quantum dot molecule and demonstrated to be indeed important. The net piezoelectric contribution is found to be critical in determining the correct energy spectrum, which is in contrast to recent studies reporting vanishing net piezoelectric contributions.     

Quasi mode theory of macroscopic canonical quantization in quantum optics and cavity quantum electrodynamics

Abstract

A macroscopic, canonical quantization of the EM field and radiating atom system in quantum optics and cavity QED involving classical, linear optical devices, based on expanding the vector potential in terms of quasi mode functions is presented. The quasi mode functions approximate the true mode functions for the device, and are obtained by solving the Helmholtz equation for an idealized spatially dependent electric permittivity function describing the device. The Hamiltonian for the EM field and radiating atom system is obtained in multipolar form and the quantum EM field is found to be equivalent to a set of quantum harmonic oscillators, one oscillator per quasi mode. However, unlike true mode theory where the quantum harmonic oscillators are uncoupled, in the quasi mode theory they are coupled and photon exchange processes can occur. Explicit expressions for the coupling constants are obtained. The interaction energy between the radiative atoms and the quantum EM field depends on the amplitudes of the quasi mode functions at the positions of the radiating atoms, similar to that for the true mode approach. The simpler forms for the quasi mode functions enable the atom-field interaction energy to be written in a form in which the atoms are only coupled to certain types of modes—for example cavity quasi modes, which are large inside the optical cavity. In such cases the escape of energy from excited atoms in the cavity can be pictured in quasi mode theory as a two step process—the atom de-excites and creates a photon in a cavity quasi mode, the photon in the cavity quasi mode is then lost and appears as a photon in an external quasi mode. In this process the first step occurs via the atom-cavity quasi mode interaction, the second through coupling between cavity and external quasi modes. This may be contrasted with the true mode approach, where the excited atom loses its energy and the photon is created in one of the true modes. As all true modes have non-zero amplitudes outside as well as inside the cavity, the escape of energy from excited atoms in the cavity is seen as a one step process. An application of the quasi mode theory to the quantum theory of the beam splitter is outlined. The unitary operator used to describe this device is a scattering operator, relating initial and long time values of annihilation, creation operators for pairs of incident and reflected modes, interpreted here as quasi modes.     

氦原子的量子力学表征

根据氢原子的量子力学表征和勒让德近似,得到氦原子的能量表示。结果表明:极限时间量子态氦原子的能量与氦原子能量的实验测定值符合。