Bidirectional optical non-reciprocity in a multi-mode cavity optomechanical system

Optical non-reciprocity, a phenomenon that allows unidirectional flow of optical field is pivoted on the time reversal symmetry breaking. The symmetry breaking happens in the cavity optomechanical system (COS) due to non uniform radiation pressure as a result of light-matter interaction, and is crucial in building non-reciprocal optical devices. In our proposed COS, we study the non-reciprocal transport of optical signals across two ports via three optical modes optomechanically coupled to the mechanical excitations of two nano-mechanical resonators (NMRs) under the influence of strong classical drive fields and weak probe fields. By tuning different system parameters, we discover the conversion of reciprocal to non-reciprocal signal transmission. We reveal perfect nonreciprocal transmission of output fields when the effective cavity detuning parameters are near resonant to the NMRs' frequencies. The unidirectional non-reciprocal signal transport is robust to the optomechanical coupling parameters at resonance conditions. Moreover, the cavities' photon loss rates play an inevitable role in the unidirectional flow of signal across the two ports. Bidirectional transmission can be fully controlled by the phase changes associated with the incoming probe and drive fields via two ports. Our scheme may provide a foundation for the compact non-reciprocal communication and quantum information processing, thus enabling new devices that route photons in unconventional ways such as all-optical diodes, optical transistors and optical switches

Effect of the enhanced recovery after surgery (ERAS®) program on postoperative complications in the Whipple operation: A prospective cohort

Background: The Whipple operation treats pancreatic, bile duct, and intestinal malignancies. ERAS® usage in the Whipple surgery is seldom documented. So, this study examined how the ERAS® regimen affected postoperative complications in Whipple patients. Method: From January 2017 to December 2022, 97 patients were admitted to the general surgery department at Hayatabad Medical Complex, Peshawar, Pakistan, a tertiary care hospital. This study recruited Whipple patients. The prospective group was treated with ERAS methods, whereas the control group was handled using the non-ERAS treatment (Jan 2017–Dec 2018). The Whipple technique was performed on 18-year-olds with pancreatic, duodenum, and bile duct cancer. The present study's primary outcomes were CDC grading, surgical complications, 30-day readmission rate, 30-day re-operation for any reason, and hospital stay. SPSS 26.0 examined data. Results: This study has 97 patients. Both groups had equal comorbidities. The ERAS® technique minimized postoperative complications, as seen by the considerable drop in CDC grading (p = 0.003). Non-ERAS® patients had increased mortality (2 vs. 8). ERAS® also decreased stay duration (p = 0.001). ERAS® patients also had a lower readmission rate (p = 0.001). Conclusion: The Whipple procedure's ERAS® protocol has lowered postoperative complications, duration of stay, and readmission rates.&nbsp