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تسجيل مستخدم جديدCoupling of ultrathin tapered fibers with high-Q microsphere resonators at cryogenic temperatures and observation of phase-shift transition from undercoupling to overcoupling
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Masazumi Fujiwara Masazumi Fujiwara
تاريخ النشر
2012
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فيزياء
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English
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We cooled ultrathin tapered fibers to cryogenic temperatures and controllably coupled them with high-Q microsphere resonators at a wavelength close to the optical transition of diamond nitrogen vacancy centers. The 310-nm-diameter tapered fibers were stably nanopositioned close to the microspheres with a positioning stability of approximately 10 nm over a temperature range of 7-28 K. A cavity-induced phase shift was observed in this temperature range, demonstrating a discrete transition from undercoupling to overcoupling.
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