We demonstrate a mode-locked, erbium-doped fiber laser with its repetition frequency synchronized to a second fiber laser via an intracavity electro-optic modulator (EOM). With servo control from the EOM (bandwidth approximately 230 kHz) and a slower speed intracavity piezoelectric transducer (resonance at approximately 20 kHz), we demonstrate stabilization of the repetition frequency with an i...

In this paper, evidence is provided that Chilean dolphins (Cephalorhynchus eutropia) produce ultrasonic echolocation clicks of the narrow-band high-frequency category. Echolocation clicks emitted during approaches of the hydrophones consisted only of narrow-band (rms-BW: 12.0 kHz) single pulses with mean centroid frequencies of about 126 kHz, peak frequencies of 126 kHz, and a 20 dB duration of...

A tunable femtosecond solid-state amplifier system that uses only 3 W of 488-nm argon-ion pump power has been demonstrated to deliver microjoule pulses at repetition rates up to 20 kHz, with a maximum pulse energy of 14 mu;J obtained at 5 kHz. An all-solid-state, tunable, diode-pumped Cr:LiSrAlF(6) regenerative amplifier has been demonstrated, for the first time to our knowledge, that amplifies...

The paper presents results of an international comparison of two quantum AC Josephson Voltage Standards based on pulse-driven Josephson arrays. The two systems differ in several hardware and software characteristics as well as in the level of automation, features which can influence the accuracy of transferring the quantum-standard voltage value to a calibrated instrument. The comparison was co...

Auditory brainstem response (ABR) and standard behavioral methods were compared by measuring in-air audiograms for an adult female harbor seal (Phoca vitulina). Behavioral audiograms were obtained using two techniques: the method of constant stimuli and the staircase method. Sensitivity was tested from 0.250 to 30 kHz. The seal showed good sensitivity from 6 to 12 kHz [best sensitivity 8.1 dB (...

Both distortion-product otoacoustic emissions (DPOAEs) and performance in an auditory-masking task involving combination tones were measured in the same frequency region in the same ears. In the behavioral task, a signal of 3.6 kHz (duration 300 ms, rise/fall time 20 ms) was masked by a 3.0-kHz tone (62 dB SPL, continuously presented). These two frequencies can produce a combination tone at 2.4...

The precise control of direct current (dc) magnetic fields is crucial in a wide range experimental platforms, from ultracold quantum gases and nuclear resonance to precision measurements. In each these cases, the Zeeman effect causes states shift energy as function field. development low-noise sources essential because electromagnets are preferred tool dynamically Here, we describe an ultra-low...

OBJECTIVES The primary goal of this study was to test the ability of 2f1-f2 distortion-product otoacoustic emissions (DPOAEs) to detect reduced cochlear function in the presence of normal behavioral sensitivity. DESIGN A prospective study was performed in normal-hearing young adults using simple and complex regression analyses to clarify the relationship between ultra-high frequency (UHF) hea...