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Single and double hole quantum dots in strained Ge/SiGe quantum wells

Journal Article · · Nanotechnology

Even as today's most prominent spin-based qubit technologies are maturing in terms of capability and sophistication, there is growing interest in exploring alternate material platforms that may provide advantages, such as enhanced qubit control, longer coherence times, and improved extensibility. Recent advances in heterostructure material growth have opened new possibilities for employing hole spins in semiconductors for qubit applications. Undoped, strained Ge/SiGe quantum wells are promising candidate hosts for hole spin-based qubits due to their low disorder, large intrinsic spin–orbit coupling strength, and absence of valley states. We use a simple one-layer gated device structure to demonstrate both a single quantum dot as well as coupling between two adjacent quantum dots. The hole effective mass in these undoped structures, m* ~ 0.08 m 0, is significantly lower than for electrons in Si/SiGe, pointing to the possibility of enhanced tunnel couplings in quantum dots and favorable qubit–qubit interactions in an industry-compatible semiconductor platform.

Research Organization:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); National Taiwan Univ., Taipei (Taiwan)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC); SNL Laboratory Directed Research and Development (LDRD) Program; Ministry of Science and Technology (MOST) (Taiwan)
Grant/Contract Number:
NA0003525; 107-2622-8-002-018
OSTI ID:
1502975
Report Number(s):
SAND2019-3007J; 673530
Journal Information:
Nanotechnology, Vol. 30, Issue 21; ISSN 0957-4484
Publisher:
IOP PublishingCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 21 works
Citation information provided by
Web of Science

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