Trapping single electrons on liquid helium
ABSTRACT Surface-state electrons on liquid helium, localised in quantum dots, have been proposed as condensed matter qubits. We now demonstrate experimentally that small numbers of electrons, including a single isolated electron, can be held in a novel electrostatic trap above the surface of superfluid helium. A potential well is created using microfabricated electrodes in a 5 μm diameter pool of helium. Electrons are injected into the trap from an electron reservoir on a helium microchannel. They are individually detected using a superconducting single-electron transistor (SET) as an electrometer. A Coulomb staircase is observed as electrons leave the trap one-by-one until the trap is empty. A design for a prototype quantum information processor using an array of electron traps on liquid helium is presented.
- SourceAvailable from: José Pedro Rino[show abstract] [hide abstract]
ABSTRACT: Using numerical simulations we investigated the dynamic response to an externally driven force of a classical two-dimensional (2D) electron system on a helium film at finite temperatures. A potential barrier located at the center of the system behaves as a pinning center that results in an insulator state below a threshold driving force. We have found that the current-voltage characteristic obeys the scaling relation I=f ξ , with ξ ranging from ∼(1.0–1.7) for different pinning strengths and temperatures. Our results may be used to understand the spread range of ξ in experiments with typical characteristic of plastic depinning. KeywordsCollective transport-Electrons in helium-Non-linear phenomenaJournal of Low Temperature Physics 160(1):58-67. · 1.18 Impact Factor
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ABSTRACT: We have observed trapping of electrons in an electrostatic trap formed over the surface of liquid 4He. These electrons are detected by a Single Electron Transistor located at the center of the trap. We can trap any desired number of electrons between 1 and ∼30. By repeatedly (∼103–104 times) putting a single electron into the trap and lowering the electrostatic barrier of the trap, we can measure the effective temperature of the electron and the time of its thermalisation after heating up by incoherent radiation.Journal of Low Temperature Physics 01/2007; 148(3):193-197. · 1.18 Impact Factor