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College educators have an implicit obligation to teach students today about optics and photonics for the jobs of tomorrow. This experiment is designed for upper-level undergraduates to work in a femtosecond laser lab. The optics are aligned prior to students arriving in the lab for ease of instruction. While performing the experiment, students are allowed to move a translation stage, which functions to overshoot or delay the arrival of the translation arm laser pulse at a nonlinear beta-barium borate (BBO) crystal relative to the arrival of the stationary arm laser pulse. Ultimately, students generate an autocorrelation of the laser pulse using second harmonic generation (SHG) from the BBO crystal and the femtosecond pulse duration. Students benefit from seeing the inner-workings of a femtosecond laser and the experimental setup. Moreover, they begin to understand SHG, consider laser applications, and get a glimpse of a possible career focus.

In this paper, we report the study of the frequency-dependent plasmonic enhancement of a circular disk nano-optical antenna array and the photo-response of the optical antenna enhanced photodetector at different frequencies using a femtosecond (fs) laser frequency comb. A fs-laser frequency comb can provide hundreds of evenly spaced harmonic frequencies and thus allows simultaneous measurement of the plasmonic optical antenna enhancement effect at these harmonic frequencies. This offers a highly efficient frequency-dependent measurement approach compared to the conventional method of modulating of a c.w. laser, which measures the frequency response at each frequency. The impulse response of the circular disk nano-optical antenna array and the electric-field (E-field) distribution profile are simulated under a fs laser illumination. The light intensity spectrum is simulated and verified to have uniform intensities on the harmonic frequencies within the ±5 GHz frequency range. The photocurrent densities in different regions of a GaAs p-i-n photodetector are analyzed together with their frequency dependence at the harmonic frequencies of the fs laser frequency comb with a repetition rate of f 0 = 94.2 MHz. A circular disk nano-optical antenna array enhanced GaAs p-i-n photodetector was fabricated and measured using a fs laser frequency comb with the same repetition rate. The nano-optical antenna can provide ~20 dB enhancement for the harmonic frequencies and extend the detector cut-off frequency from 2.4 GHz to 4.2 GHz.

Purpose of Project: The purpose of the inpatient psychiatric unit denials reduction project was to establish a taskforce to analyze denials data for root cause and identify an effective solution to prevent denials through improved provider documentation. Primary Practice Setting: The development and implementation of the project occurred at Stanford Health Care, a nonprofit Level 1 trauma hospital, with a 29-bed inpatient psychiatric unit containing both open and secured levels of care. The project was led by the Utilization/Denials Management team, which is subteam within the Case Management Department. Team members are Nurse Case Managers specializing in the management of denials and appeals, data analysis and trending of denials, denial avoidance, and reduction of financial risk. Methodology: Denials data analysis revealed the Psychiatry Service Line was responsible for over 70% of payer denials within the Length of Stay Write-offs category. In early 2019, the Utilization/Denials Management team initiated a quality improvement project using A3 Lean Approach methodology and evidence-based practice to guide the implementation. The partnership and collaboration included Case Management, Revenue Cycle, Clinical Documentation Improvement, Technology and Digital Solutions, and Psychiatry Service Line leadership that had an interest in reducing payer denials. Results: Outcomes measured for the project were based on denials data for (fiscal year) FY19, the preintervention period, compared to FY20 and FY21, the postintervention period. From FY19 to FY20, revenue loss decreased by 42%. The downward trend continued from FY20 to FY21 with a recorded decrease by 69%. Implications for Case Management Practice: The most important implication of the project was improved physician documentation and medical necessity supporting the severity and intensity of inpatient psychiatric level of care, and medical justification for the inpatient stay not only to prevent medical necessity denials but to accurately reflect the care that was provided. High-quality documentation correlates to the high quality of care being provided. This project is far reaching not only for psychiatric units but also reproducible for other acute hospital service lines. Case Management is a multidisciplinary role, and this work is most meaningful for a Nurse Case Manager engaged in care coordination, including utilization and denials management.