Role elektrod v efektu chiralitou indukované spinové selektivity
| Thesis title in Czech: | Role elektrod v efektu chiralitou indukované spinové selektivity |
|---|---|
| Thesis title in English: | The role of leads in the effect of chirality induced spin selectivity |
| Academic year of topic announcement: | 2024/2025 |
| Thesis type: | Bachelor's thesis |
| Thesis language: | |
| Department: | Department of Condensed Matter Physics (32-KFKL) |
| Supervisor: | RNDr. Martin Žonda, Ph.D. |
| Author: |
| Guidelines |
| The student will:
1. learn the basics of transport theory, 2. understand and be able to construct Hamiltonians of simple models written in the language of creation and annihilation operators 3. will learn to write hers/his own code in Python using the transport package KWANT 4. will provide hers/his own research on an open, unsolved problem, with numerous possible applications |
| References |
| Basics of transport theory:
Electronic transport in mesoscopic systems; Supriyo Datta KWANT: https://kwant-project.org/doc/ CISS: https://inference-review.com/article/chiral-induced-spin-selectivity A Chirality-Based Quantum Leap: A Forward-Looking Review, https://arxiv.org/abs/2009.00136 |
| Preliminary scope of work |
| An unusually large spin polarization of the charge current was
observed experimentally in chiral organic molecule systems like double-stranded DNA, oligopeptides,polyalamines or helicene chains. This intriguing phenomenon of chiral induced spin selectivity (CISS) means that there is a strong preference towards a one-way passage of electrons with one spin orientation (e.g., “up”) to the other “down” in systems in systems where it was not expected. Despite tremendous theoretical and experimental effort, motivated by numerous possible applications, there is still no consensus on the underlying physical mechanism behind this effect. However, the research suggests, that to decipher the mysterious CISS effect, we need to firstly understand how it is influenced by the leads involved in the transport measurements. The student will focus on experimentally relevant case of leads with finite spin-orbit coupling and investigate its influence on the CISS effect. To this goal the student will learn to work with the transport code KWANT, namely how to construct basic tight-binding Hamiltonian coupled to metallic leads and how to calculate transmission characteristics. The student will write his/hers own script, will get familiar with the basics properties of simple CISS model system and then will investigate the influence of spin-orbit coupling in the leads on the equilibrium transmission function. |
| Preliminary scope of work in English |
| An unusually large spin polarization of the charge current was
observed experimentally in chiral organic molecule systems like double-stranded DNA, oligopeptides,polyalamines or helicene chains. This intriguing phenomenon of chiral induced spin selectivity (CISS) means that there is a strong preference towards a one-way passage of electrons with one spin orientation (e.g., “up”) to the other “down” in systems in systems where it was not expected. Despite tremendous theoretical and experimental effort, motivated by numerous possible applications, there is still no consensus on the underlying physical mechanism behind this effect. However, the research suggests, that to decipher the mysterious CISS effect, we need to firstly understand how it is influenced by the leads involved in the transport measurements. The student will focus on experimentally relevant case of leads with finite spin-orbit coupling and investigate its influence on the CISS effect. To this goal the student will learn to work with the transport code KWANT, namely how to construct basic tight-binding Hamiltonian coupled to metallic leads and how to calculate transmission characteristics. The student will write his/hers own script, will get familiar with the basics properties of simple CISS model system and then will investigate the influence of spin-orbit coupling in the leads on the equilibrium transmission function. |