Phys Rev A (Coll Park)
June 2020
Many quantum state preparation methods rely on a combination of dissipative quantum state initialization followed by unitary evolution to a desired target state. Here we demonstrate the usefulness of quantum measurement as an additional tool for quantum state preparation. Starting from a pure separable multipartite state, a control sequence, which includes rotation, spin squeezing via one-axis twisting, quantum measurement, and postselection, generates highly entangled multipartite states, which we refer to as (PS) states.
View Article and Find Full Text PDFCurr Opin Otolaryngol Head Neck Surg
August 2018
Purpose Of Review: Tremendous advancements have been made in head and neck reconstruction following oncologic resection. Despite this, many patients are left with disfiguring postoperative changes. The focus of this review highlights various techniques aimed at improving aesthetic outcomes following head and neck cancer therapy, with a focus on liposuction and fat augmentation.
View Article and Find Full Text PDFWe introduce concepts from optimal estimation to the stabilization of precision frequency standards limited by noisy local oscillators. We develop a theoretical framework casting various measures for frequency standard variance in terms of frequency-domain transfer functions, capturing the effects of feedback stabilization via a time series of Ramsey measurements. Using this framework, we introduce an optimized hybrid predictive feedforward measurement protocol that employs results from multiple past measurements and transfer-function-based calculations of measurement covariance to improve the accuracy of corrections within the feedback loop.
View Article and Find Full Text PDFWe have demonstrated simultaneous laser frequency stabilization of a UV and IR laser, to coupled transitions of ions in the same spectroscopic sample, by detecting only the absorption of the UV laser. Separate signals for locking the different lasers are obtained by modulating each laser at a different frequency and using lock-in detection of a single photodiode signal. Experimentally, we simultaneously lock a 369 nm and a 935 nm laser to the (2)S(1/2) → (2)(P(1/2) and (2)D(3/2) → (3)D([3/2]1/2) transitions, respectively, of Yb(+) ions generated in a hollow cathode discharge lamp.
View Article and Find Full Text PDFAfr J Psychiatry (Johannesbg)
January 2013
Objective: Literature on the prevalence and clinical presentation of South African psychiatric HIV positive patients as well as their management is lacking. This study was performed to investigate these parameters.
Method: A prospective study to investigate the prevalence and clinical presentation of HIV positive psychiatric female patients admitted to an acute ward (female psychiatric ward Cecilia Makiwane Hospital, East London Hospital Complex) was undertaken for a one year period from June 2009 to May 2010.