Performance optimization analysis of a thermoelectric refrigerator with two resonances

Based on electron transport theory,the performance of k x and k r filtered thermoelectric refrigerators with two resonances are studied in this paper.The performance characteristic curves between the cooling rate and the coefficient of performance are plotted by numerical calculation.It is shown that the maximum cooling rate of the thermoelectric refrigerator with two resonances increases but the maximum coefficient of performance decreases compared with those with one resonance.No matter which resonance mechanism is used(k x or k r filtered),the cooling rate and the performance coefficient of the k r filtered refrigerator are much better than those of the k x filtered one.     

Solid-state resonant tunneling thermoelectric refrigeration in the cylindrical double-barrier nanostructure

A solid-state thermoelectric refrigerator with a cylindrical InP/InAs/InP double-barrier heterostructure is proposed.Based on the ballistic electron transport and the asymmetrical transmission, we derive the expressions of the performance parameters of this refrigerator. The cooling rate rather than the coefficient of performance is affected by the area of the inner cylinder. Then through the numerical simulation, a triangular cooling rate region is found with respect to the chemical potential and bias voltage; further, that it is because of the small full width at half maximum of the transmission resonance and the linear relationship between the energy position of resonance and the bias voltage. These tunable results might supply some guide to the cooling in tiny components or devices.     

摇摆型棘齿热电子隧穿制冷

本文利用传输矩阵法数值模拟了电子在加入周期性正负偏压的双势垒("摇摆"棘齿)异质结中的传输特性,获得了两电子库间的净电流以及所伴随的净热流的表达式.进一步分析了净电流、净热流和制冷系数等性能参数的特征,获得的结果对介观热电子器件的研制有一定的理论指导意义. 关键词： 热电子制冷机 摇摆棘齿 性能参数 传输矩阵法     

Carrier and magnetism engineering for monolayer SnS2 by high throughput first-principles calculations

Two-dimensional (2D) semiconducting tin disulfide (SnS₂) has been widely used for optoelectronic applications. To functionalize SnS₂ for extending its application, we investigate the stability, electronic and magnetic properties of substitutional doping by high throughput first-principles calculations. There are a lot of elements that can be doped in monolayer SnS₂. Nonmetal in group A can introduce p-type and n-type carriers, while most metals in group A can only lead to p-type doping. Not only 3d, but also 4d and 5d transition metals in groups VB to VⅢB9 can introduce magnetism in SnS₂, which is potentially applicable for spintronics. This study provides a comprehensive view of functionalization of SnS₂ by substitutional doping, which will guide further experimental realization.     

氧化铟锡纳米阵列中的协同增强拉曼散射现象研究

一些具有表面增强拉曼散射(Surface-enhanced Raman Scattering,SERS)性能的金属氧化物材料近年来被广泛研究,它们具有相较于传统贵金属材料更为优异的信号均匀度、材料稳定性和生物兼容性等.目前金属氧化物SERS的研究瓶颈在于拉曼增强效果一般,需要对其检测灵敏度进行有效提升方可实现日后的广泛...