Valley Splitting in a Silicon Quantum Device Platform
By suppressing an undesirable surface Umklapp process, it is possible to resolve the two most occupied states (1Г and 2 Г) in a buried two-dimensional electron gas (2DEG) in silicon. The 2DEG exists because of an atomically sharp profile of phosphorus dopants which have been formed beneath the Si(00...
| Main Authors: | , , , , , , |
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| Format: | Journal Article |
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American Chemical Society
2014
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| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.11937/34200 |
| _version_ | 1848754157934084096 |
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| author | Miwa, J. Warchkow, O. Carter, Damien Marks, Nigel Mazzola, F. Simmons, M. Wells, J. |
| author_facet | Miwa, J. Warchkow, O. Carter, Damien Marks, Nigel Mazzola, F. Simmons, M. Wells, J. |
| author_sort | Miwa, J. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | By suppressing an undesirable surface Umklapp process, it is possible to resolve the two most occupied states (1Г and 2 Г) in a buried two-dimensional electron gas (2DEG) in silicon. The 2DEG exists because of an atomically sharp profile of phosphorus dopants which have been formed beneath the Si(001) surface (a δ -layer). The energy separation, or valley splitting, of the two most occupied bands has critical implications for the properties of δ -layer derived devices, yet until now, has not been directly measurable. Density functional theory (DFT) allows the 2DEG band structure to be calculated, but without experimental verification the size of the valley splitting has been unclear. Using a combination of direct spectroscopic measurements and DFT we show that the measured band structure is in good qualitative agreement with calculations and reveal a valley splitting of 132 ± 5 meV. We also report the effective mass and occupation of the 2DEG states and compare the dispersions and Fermi surface with DFT. |
| first_indexed | 2025-11-14T08:35:57Z |
| format | Journal Article |
| id | curtin-20.500.11937-34200 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:35:57Z |
| publishDate | 2014 |
| publisher | American Chemical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-342002017-09-13T15:10:07Z Valley Splitting in a Silicon Quantum Device Platform Miwa, J. Warchkow, O. Carter, Damien Marks, Nigel Mazzola, F. Simmons, M. Wells, J. valley-splitting quantum computer Umklapp ARPES silicon δ-layer By suppressing an undesirable surface Umklapp process, it is possible to resolve the two most occupied states (1Г and 2 Г) in a buried two-dimensional electron gas (2DEG) in silicon. The 2DEG exists because of an atomically sharp profile of phosphorus dopants which have been formed beneath the Si(001) surface (a δ -layer). The energy separation, or valley splitting, of the two most occupied bands has critical implications for the properties of δ -layer derived devices, yet until now, has not been directly measurable. Density functional theory (DFT) allows the 2DEG band structure to be calculated, but without experimental verification the size of the valley splitting has been unclear. Using a combination of direct spectroscopic measurements and DFT we show that the measured band structure is in good qualitative agreement with calculations and reveal a valley splitting of 132 ± 5 meV. We also report the effective mass and occupation of the 2DEG states and compare the dispersions and Fermi surface with DFT. 2014 Journal Article http://hdl.handle.net/20.500.11937/34200 10.1021/nl404738j American Chemical Society restricted |
| spellingShingle | valley-splitting quantum computer Umklapp ARPES silicon δ-layer Miwa, J. Warchkow, O. Carter, Damien Marks, Nigel Mazzola, F. Simmons, M. Wells, J. Valley Splitting in a Silicon Quantum Device Platform |
| title | Valley Splitting in a Silicon Quantum Device Platform |
| title_full | Valley Splitting in a Silicon Quantum Device Platform |
| title_fullStr | Valley Splitting in a Silicon Quantum Device Platform |
| title_full_unstemmed | Valley Splitting in a Silicon Quantum Device Platform |
| title_short | Valley Splitting in a Silicon Quantum Device Platform |
| title_sort | valley splitting in a silicon quantum device platform |
| topic | valley-splitting quantum computer Umklapp ARPES silicon δ-layer |
| url | http://hdl.handle.net/20.500.11937/34200 |