Measurement of Tunnel Coupling in a Si Double Quantum dot Based on Charge Sensing

Tunnel coupling is a key parameter in coupled semiconductor quantum dots, and crucial ingredient various device applications, such as exchange gates spin shuttling information processing. A widely used charge-sensing technique to extract the tunnel of double dot accounts for only ground orbital state each dot, but authors show that Si valley-orbit must be included analysis. With their more complete model, one can not $i\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}v\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}y$ (ground-state) accurately, also obtain on $i\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}r\phantom{\rule{0}{0ex}}v\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}e\phantom{\rule{0}{0ex}}y$ (ground-to-excited-state) coupling.