Production of germanium stable isotopes single crystals

Abstract

It is reported on production of germanium stable isotopes 72 Ge, 73 Ge, 74 Ge, 76 Ge single crystals with high isotopic and chemical purity by hydride method. Separation of isotopes was carried out by centrifugal method using monogermane as the initial volatile substance. Samples of monoisotopic monogermanes 72 GeH 4 , 73 GeH 4 , 74 GeH 4 , 76 GeH 4 were purified by the method of low-temperature rectification. Elementary polycrystalline germanium was extracted by pyrolysis from respective monogermane and purified from impurities by the method of zone melting. Single crystals of germanium isotopes were grown by Czochralski method. The content of the main isotope in the produced single crystals 72 Ge, 73 Ge, 74 Ge, 76 Ge was 99.98; 99.90; 99.93 and 87.5 at. %, respectively, and the content of the impurities of stable elements was less than 10 −5 -10 −6 mass %.

Characterization of Shallow, Undoped Ge/SiGe Quantum Wells Commercially Grown on 8-in. (100) Si Wafers

“…Holes in Ge/SiGe quantum well heterostructures have been shown to have excellent transport properties such as low percolation densities of around 2.1 × 10 10 cm –2 and peak mobilities of around 1 × 10 6 cm 2 V –1 s –1 at a temperature of 1.7 K, indicating low levels of disorder. Specifically, holes in Ge are attractive because the large spin–orbit interaction allows electric control of the spin, , while the p-like orbital symmetry of holes is expected to be robust against hyperfine interactions, which can be further suppressed through isotopic purification of Ge. , For qubit applications, further potential advantages of holes in Ge, compared to electrons in Si, include a small effective mass which relaxes fabrication constraints, lack of valley degeneracy in the valence band, and large out-of-plane and tunable effective g -factors. , Altogether, these properties make Ge/SiGe quantum well heterostructures a leading candidate for quantum processors with demonstrations of singlet–triplet qubits and single-hole qubits up to a four-qubit quantum processor …”

Coupling a Germanium Hut Wire Hole Quantum Dot to a Superconducting Microwave Resonator

“…The photon loss rate κ/2π could be decreased by optimizing the substrate and resonator. As a group IV material, isotropic purified germanium , might have an even smaller decoherence rate γ/2π, and this technique has been performed on silicon. , With these optimized schemes in the future work, we anticipate that the strong spin–resonator coupling is viable in hole QD based on the Ge hut wire system.…”

Изотопический Сдвиг ИК Полос Поглощения Монокристаллов Германия

“…Монокристаллы изотопов германия выращивали в лаборатории Института роста кристаллов (IKZ, Берлин) методом Чохральского из кварцевого тигля в среде высокочистого аргона. Монокристаллы выращивали в кристаллографическом направлении 100 ; диаметр кристаллов составлял 13−17 mm [14,34].…”