{"title":"半导体硅-硅-锗自旋 Qubits 中的声子诱导交换栅不忠实现象","authors":"Matthew Brooks, Rex Lundgren, Charles Tahan","doi":"arxiv-2408.02742","DOIUrl":null,"url":null,"abstract":"Spin-spin exchange interactions between semiconductor spin qubits allow for\nfast single and two-qubit gates. During exchange, coupling of the qubits to a\nsurrounding phonon bath may cause errors in the resulting gate. Here, the\nfidelities of exchange operations with semiconductor double quantum dot spin\nqubits in a Si-SiGe heterostructure coupled to a finite temperature phonon bath\nare considered. By employing a master equation approach, the isolated effect of\neach spin-phonon coupling term may be resolved, as well as leakage errors of\nencoded qubit operations. As the temperature is increased, a crossover is\nobserved from where the primary source of error is due to a phonon induced\nperturbation of the two electron spin states, to one where the phonon induced\ncoupling to an excited orbital state becomes the dominant error. Additionally,\nit is shown that a simple trade-off in pulse shape and length can improve\nrobustness to spin-phonon induced errors during gate operations by up to an\norder of magnitude. Our results suggest that for elevated temperatures within\n200-300 mK, exchange gate operations are not currently limited by bulk phonons.\nThis is consistent with recent experiments.","PeriodicalId":501211,"journal":{"name":"arXiv - PHYS - Other Condensed Matter","volume":"16 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Phonon-Induced Exchange Gate Infidelities in Semiconducting Si-SiGe Spin Qubits\",\"authors\":\"Matthew Brooks, Rex Lundgren, Charles Tahan\",\"doi\":\"arxiv-2408.02742\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Spin-spin exchange interactions between semiconductor spin qubits allow for\\nfast single and two-qubit gates. During exchange, coupling of the qubits to a\\nsurrounding phonon bath may cause errors in the resulting gate. Here, the\\nfidelities of exchange operations with semiconductor double quantum dot spin\\nqubits in a Si-SiGe heterostructure coupled to a finite temperature phonon bath\\nare considered. By employing a master equation approach, the isolated effect of\\neach spin-phonon coupling term may be resolved, as well as leakage errors of\\nencoded qubit operations. As the temperature is increased, a crossover is\\nobserved from where the primary source of error is due to a phonon induced\\nperturbation of the two electron spin states, to one where the phonon induced\\ncoupling to an excited orbital state becomes the dominant error. Additionally,\\nit is shown that a simple trade-off in pulse shape and length can improve\\nrobustness to spin-phonon induced errors during gate operations by up to an\\norder of magnitude. Our results suggest that for elevated temperatures within\\n200-300 mK, exchange gate operations are not currently limited by bulk phonons.\\nThis is consistent with recent experiments.\",\"PeriodicalId\":501211,\"journal\":{\"name\":\"arXiv - PHYS - Other Condensed Matter\",\"volume\":\"16 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-08-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv - PHYS - Other Condensed Matter\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/arxiv-2408.02742\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - PHYS - Other Condensed Matter","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2408.02742","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Phonon-Induced Exchange Gate Infidelities in Semiconducting Si-SiGe Spin Qubits
Spin-spin exchange interactions between semiconductor spin qubits allow for
fast single and two-qubit gates. During exchange, coupling of the qubits to a
surrounding phonon bath may cause errors in the resulting gate. Here, the
fidelities of exchange operations with semiconductor double quantum dot spin
qubits in a Si-SiGe heterostructure coupled to a finite temperature phonon bath
are considered. By employing a master equation approach, the isolated effect of
each spin-phonon coupling term may be resolved, as well as leakage errors of
encoded qubit operations. As the temperature is increased, a crossover is
observed from where the primary source of error is due to a phonon induced
perturbation of the two electron spin states, to one where the phonon induced
coupling to an excited orbital state becomes the dominant error. Additionally,
it is shown that a simple trade-off in pulse shape and length can improve
robustness to spin-phonon induced errors during gate operations by up to an
order of magnitude. Our results suggest that for elevated temperatures within
200-300 mK, exchange gate operations are not currently limited by bulk phonons.
This is consistent with recent experiments.