1999/11/15 by B. Jouault, Giuseppe E. Santoro, G. Santoro +1
Physics and Astronomy · #Condensed matter physics #Conductance #Degeneracy (biology) #Electron #Ground state #Magnetic field #Physics #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Quantum dot #Quantum mechanics #Semiconductor Quantum Structures and Devices #Singlet state #Spin (aerodynamics) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.61.10242
6 pages, 5 figures, 1 table
arxiv created 1999/11/15 · openalex publication_date 2000/04/15 · arxiv updated 2016/08/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We have calculated the linear magnetoconductance across a vertical parabolic quantum dot with a magnetic field in the direction of the current. Gate voltage and magnetic field are tuned at the degeneracy point between the occupancies N=2 and N=3, close to the singlet-triplet transition for N=2. We find that the conductance is enhanced prior to the transition by nearby crossings of the levels of the three-particle dot. Immediately after it is depressed by roughly 1/3, as long as the total spin S of the three-electron ground state doesn't change from S=1/2 to S=3/2, due to spin selection rule. At low temperature this dip is very sharp, but the peak is recovered by increasing the temperature.