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تسجيل مستخدم جديدPossible use of a Cooper-pair box for low-dose electron microscopy
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Hiroshi Okamoto
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A transmission electron microscope that takes advantage of superconducting quantum circuitry is proposed. The microscope is designed to improve image contrast of radiation-sensitive weak phase objects, in particular biological specimens. The objective in this setting is to measure the phase shift of the probe electron wave to a precision $Deltatheta$ within the number of electrons $N$ that does not destroy the specimen. In conventional electron microscopy $Deltatheta$ scales as $sim 1/N^{1/2}$, which falls short of the Heisenberg limit $sim 1/N$. To approach the latter by using quantum entanglement, we propose a design that involves a Cooper pair box placed on the surface of an electrostatic electron mirror in the microscope. Significant improvement could be attained if inelastic scattering processes are sufficiently delocalized.
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This Comment has been withdrawn according to a mutual agreement between the authors of the original paper and the authors of this Comment.
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