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arXiv · 1502.03021

Thermal Gating of Charge Currents with Coulomb Coupled Quantum Dots

Holger Thierschmann·Fabian Arnold·Marcel Mittermüller·Luis Maier·Christian Heyn·Wolfgang Hansen·Hartmut Buhmann·Laurens W. Molenkamp
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Abstract

We have observed thermal gating, i.e. electrostatic gating induced by hot electrons. The effect occurs in a device consisting of two capacitively coupled quantum dots. The double dot system is coupled to a hot electron reservoir on one side (QD1), whilst the conductance of the second dot (QD2) is monitored. When a bias across QD2 is applied we observe a current which is strongly dependent on the temperature of the heat reservoir. This current can be either enhanced or suppressed, depending on the relative energetic alignment of the QD levels. Thus, the system can be used to control a charge current by hot electrons.

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Holger Thierschmann, Fabian Arnold, Marcel Mittermüller, Luis Maier, Christian Heyn, Wolfgang Hansen, Hartmut Buhmann, Laurens W. Molenkamp. 2015-02-10. Thermal Gating of Charge Currents with Coulomb Coupled Quantum Dots. https://doi.org/10.1088/1367-2630/17/11/113003

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