相关论文: Light-hole spin confined in germanium

Unlike cubic GeSn, which requires a high Sn concentration to undergo an indirect-to-direct bandgap transition, lonsdaleite (2H) germanium is an intrinsic direct-gap semiconductor. We employ first-principles density functional theory to…

Planar germanium heterostructures hosting hole-spin qubits are among the leading platforms for scalable semiconductor-based quantum computing. Yet, device performance is hindered by significant quantum dot variability, which leads to…

We study the low-energy spectrum of a single hole confined in a planar Ge quantum dot (QD) within the effective-mass formalism. The QD is sandwiched between two GeSi barriers of finite potential height grown along the [001] direction. To…

We have studied theoretically the effect of a tuneable lateral confinement on two-dimensional hole systems realised in III-V semiconductor heterostructures. Based on the 4x4 Luttinger description of the valence band, we have calculated…

The dispersion of Rashba-split heavy-hole subbands in GaAs two-dimensional hole gases (2DHGs) is difficult to access experimentally because strong heavy-hole-light-hole mixing produces non-parabolicity and breaks the usual correspondence…

Gate-controllable spin-orbit coupling is often one requisite for spintronic devices. For practical spin field-effect transistors, another essential requirement is ballistic spin transport, where the spin precession length is shorter than…

Planar semiconductor heterostructures offer versatile device designs and are promising candidates for scalable quantum computing. Notably, heterostructures based on strained germanium have been extensively studied in recent years, with…

Hole spin relaxation in [001] strained asymmetric Si/Si$_{0.7}$Ge$_{0.3}$ (Ge/Si$_{0.3}$Ge$_{0.7}$) quantum wells is investigated in the situation with only the lowest hole subband being relevant. The effective Hamiltonian of the lowest…

The p-symmetry of the hole wavefunction is associated with a weaker hyperfine interaction as compared to electrons, thus making hole spin qubits attractive candidates to implement long coherence quantum processors. However, recent studies…

The coherence of hole spin qubits in germanium planar heterostructures is limited by the hyperfine coupling to the nuclear spin bath due to 29Si and 73Ge isotopes. Thus, removing these nuclear spin-full isotopes is essential to extend the…

Spintronics, quantum computing and quantum communication science utilizing cubic semiconductors rely largely on the properties of the hole states, composed of light and heavy hole wavefunction components. The admixture of light-hole (LH)…

Hole spin qubits in planar germanium heterostructures are frontrunners for scalable semiconductor quantum computing. However, their current performance is mostly limited by large dot-to-dot variability that leads to uncontrolled qubit…

We engineer planar Ge/SiGe heterostructures for low disorder and quiet hole quantum dot operation by positioning the strained Ge channel 55~nm below the semiconductor/dielectric interface. In heterostructure field effect transistors, we…

Qubits encoded in the spin state of heavy holes confined in Si- and Ge-based semiconductor quantum dots are currently leading the efforts toward spin-based quantum information processing. The virtual absence of spinful nuclei in purified…

We derive an effective Hamiltonian for a (001)-confined quasi-two-dimensional hole gas in a strained zincblende semiconductor heterostructure including both Rashba and Dresselhaus spin-orbit coupling. In the presence of uniaxial strain…

We theoretically investigate heavy-hole--light-hole mixing in two-dimensional hole gases (2DHG). We restrict our analysis to the zone center, appropriate for the low-density regime, which leads to a simple description, analytical results,…

Spin qubits are fundamental building blocks of modern quantum computing devices. The path of Ge-based hole-spin qubits has several advantages over Si-based electron-spin systems, such as the absence of valley band degeneracy, the…

The pseudospin of heavy-holes (HHs) confined in a semiconductor quantum dot (QD) represents a promising candidate for a fast and robust qubit. While hole spin manipulation by a classical electric field utilizing the Dresselhaus spin-orbit…

Relativistic effects influence the motion of charged particles in solids by intertwining spin and momentum. The resulting phenomena exhibit rich and intriguing properties that can unveil radically new quantum devices. In this context, the…

Germanium hole spin qubits based on strained Ge/SiGe quantum well have attracted much research attention due to the strong spin-orbit coupling. In particular, the strain dependence of the heavy-hole--light-hole mixing and thus the…