Martínez-Rojas Patricia, Benavides-Vergara M Esperanza, Peña Francisco J, Vargas Patricio
Departamento de Física, CEDENNA, Universidad Técnica Federico Santa María, Av. España 1680, Valparaíso 11520, Chile.
Departamento de Física, Universidad Técnica Federico Santa María, Av. España 1680, Valparaíso 11520, Chile.
Nanomaterials (Basel). 2023 Oct 6;13(19):2714. doi: 10.3390/nano13192714.
In this work, we report the caloric effect for an electronic system of the antidot type, modeled by combining a repulsive and attractive potential (parabolic confinement). In this system, we consider the action of a perpendicular external magnetic field and the possibility of having an Aharonov-Bohm flux (AB-flux) generated by a current passing through a solenoid placed inside the forbidden zone for the electron. The energy levels are obtained analytically, and the model is known as the Bogachek and Landman model. We propose to control the caloric response of the system by varying only the AB-flux, finding that, in the absence of an external magnetic field, the maximization of the effect always occurs at the same AB-flux intensity, independently of the temperature, while fixing the external magnetic field at a non-zero value breaks this symmetry and changes the point where the caloric phenomenon is maximized and is different depending on the temperature to which the process is carried. Our calculations indicate that using an effective electron mass of GaAs heterostructures and a trap intensity of the order of 2.896 meV, the modification of the AB-flux achieves a variation in temperature of the order of 1 K. Our analysis suggests that increasing the parabolic confinement twofold increases the effect threefold, while increasing the antidot size generates the reverse effect, i.e., a strong decrease in the caloric phenomenon under study. Due to the great diversity in technological applications that have antidots in electronics, the possibility of controlling their thermal response simply by varying the intensity of the internal current inside the solenoid (i.e., the intensity of AB-flux) can be a platform of interest for experimental studies.
在这项工作中,我们报告了一种反点型电子系统的热效应,该系统通过结合排斥势和吸引势(抛物线限制)进行建模。在这个系统中,我们考虑垂直外部磁场的作用以及由穿过放置在电子禁区内的螺线管的电流产生阿哈罗诺夫 - 玻姆通量(AB通量)的可能性。能量级通过解析得到,该模型被称为博加切克和兰德曼模型。我们提议仅通过改变AB通量来控制系统的热响应,发现在没有外部磁场的情况下,效应的最大化总是发生在相同的AB通量强度下,与温度无关,而将外部磁场固定在非零值会打破这种对称性,并改变热现象最大化的点,且该点取决于过程所进行的温度。我们的计算表明,使用砷化镓异质结构的有效电子质量和2.896毫电子伏特量级的陷阱强度,AB通量的改变实现了约1K的温度变化。我们的分析表明,将抛物线限制增加两倍会使效应增加三倍,而增加反点尺寸会产生相反的效果,即在研究的热现象中大幅下降。由于电子学中具有反点的技术应用种类繁多,仅通过改变螺线管内部电流强度(即AB通量强度)来控制其热响应的可能性可能是一个值得进行实验研究的平台。