Wiring up single electron traps to perform quantum gates

Abstract

Two quantum oscillators coupled with a planar radio frequency ion trap Chen Liang and Gao Ke-Lin -Review I Marzoli, P Tombesi, G Ciaramicoli et al. Abstract. Two electrons in planar Penning traps can be coupled by connecting the trap electrodes with a metallic wire. The wire provides a capacitive and resistive link between the image charges that the electron oscillation (axial motion) is inducing in the electrodes. This can be operated as a quantum network to transfer excitation quanta between the traps and to entangle the two electrons. We give a detailed analysis of this system in the dispersive limit and assess the impact of resistive thermal noise. The latter is found to be remarkably small at temperatures below 4 K in miniaturized planar traps (sizes below 1 mm). The master equation for the two-electron system in the presence of resistive noise is solved exactly. We compute fidelities for basic quantum gates needed in quantum information processing.

Quantum Interfaces Between Atomic and Solid-State Systems

“…3c. This type of bus has been proposed for interconnecting electrons trapped in Penning traps to ions [15], Rydberg atoms to each other [39], trapped ions to superconducting charge qubits [72], electrons trapped in Penning traps to each other [73,74], trapped ions in Paul traps to each other [75] and charged nanobeams [76]. The capacitive bus falls in-between the two categories mentioned above.…”

Experimental and theoretical challenges for the trapped electron quantum computer

“…The qubit bases mentioned above allow for various types of conditional qubit dynamics [22,52]. Here we restrict ourselves to scalable methods and focus on a direct spin-spin interaction mediated by a magnetic field gradient and by an electrical coupling of the electrons axial motion via a direct connection of trap electrodes.…”

“…In the low-frequency regime the wire mainly acts as a capacitive coupler. The coherent coupling is described by the Hamiltonian where a and a † denote the creation and annihilation of axial quanta, and the Rabi frequency [52]…”

“…The capacitance C 0 ∼ πε 0 R 0 describes the intrinsic electrode capacitance and C w is the capacitance of the wire connecting the two traps. The shorter the wire (C w decreases) and the smaller the trap electrodes (R 0 and C 0 decrease), the stronger the coherent coupling [52]. Typical values are quoted in Table 2.…”

Coupling two laser-cooled ions via a room-temperature conductor

“…In conclusion, we have established coupling between two remotely trapped ions enhanced via a solid-state wire at room temperature. In principle, the wire-mediated coupling design opens new avenues to cool, detect, or otherwise couple remotely trapped charged particles such as antiprotons [16,33] or electrons [21,34]. In fact, this scheme is particularly attractive for electrons, as the coupling strength increases by two orders of magnitude when replacing 40 Ca + ions with trapped electrons at 100 MHz trap frequency.…”