Effective out-of-plane g-factor in strained-Ge/SiGe quantum dots

Abstract

Recently, lithographic quantum dots in strained-Ge/SiGe have become a promising candidate for quantum computation, with a remarkably quick progression from demonstration of a quantum dot to qubit logic demonstrations. Here we present a measurement of the out-of-plane $g$-factor for single-hole quantum dots in this material. As this is a single-hole measurement, this is the first experimental result that avoids the strong orbital effects present in the out-of-plane configuration. In addition to verifying the expected $g$-factor anisotropy between in-plane and out-of-plane magnetic ($B$)-fields, variations in the $g$-factor dependent on the occupation of the quantum dot are observed. These results are in good agreement with calculations of the $g$-factor using the heavy- and light-hole spaces of the Luttinger Hamiltonian, especially the first two holes, showing a strong spin-orbit coupling and suggesting dramatic $g$-factor tunability through both the $B$-field and the charge state.

References in corpus (8)

• An addressable quantum dot qubit with fault-tolerant control fidelity
• Computing with spin qubits at the surface code error threshold
• Two-qubit silicon quantum processor with operation fidelity exceeding 99%
• Electric Dipole Spin Resonance for Heavy Holes in Quantum Dots
• Cubic Rashba spin-orbit interaction of two-dimensional hole gas in strained-Ge/SiGe quantum well
• Simple model for electrical hole spin manipulation in semiconductor quantum dots: Impact of dot material and orientation
• Effective g factor of low-density two-dimensional holes in a Ge quantum well
• Assessing the potential of Ge/SiGe quantum dots as hosts for singlet-triplet qubits

Cited by in corpus (3)

• Fermion-parity qubit in a proximitized double quantum dot
• Probing details of spin--orbit coupling through Pauli spin blockade
• Disentangling orbital and confinement contributions to $g$-factor in Ge/SiGe hole quantum dots