Faculty Type: 
Active Faculty
Professor (research)
Physics and Astrophysics Bldg. Rm. 221
452 Lomita Mall
Stanford University
Stanford, CA 94305
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How can we make optimal use of quantum systems (atoms, lasers, and electronics) to test fundamental physics principles, enable precision measurements of space-time and when feasible, develop useful devices, sensors, and instruments?

Professor Hollberg’s research objectives include high precision tests of fundamental physics as well as applications of laser physics and technology. This experimental program in laser/atomic physics focuses on high-resolution spectroscopy of laser-cooled and -trapped atoms, non-linear optical coherence effects in atoms, optical frequency combs, optical/microwave atomic clocks, and high sensitivity trace gas detection. Frequently this involves the study of laser noise and methods to circumvent measurement limitations, up to, and beyond, quantum limited optical detection. Technologies and tools utilized include frequency-stabilized lasers and chip-scale atomic devices. Based in the Hansen Experimental Physics Laboratory (HEPL), this research program has strong, synergistic, collaborative connections to the Stanford Center on Position Navigation and Time (SCPNT). Research directions are inspired by experience that deeper understanding of fundamental science is critical and vital in addressing real-world problems, for example in the environment, energy, and navigation. Amazing new technologies and devices enable experiments that test fundamental principles with high precision and sometimes lead to the development of better instruments and sensors. Ultrasensitive optical detection of atoms, monitoring of trace gases, isotopes, and chemicals can impact many fields. Results from well-designed experiments teach us about the “realities” of nature, guide and inform, occasionally produce new discoveries, frequently surprise, and almost always generate new questions and perspectives.

Current areas of focus:

  • Laser-cooled atoms for tests of fundamental physics and optical atomic clocks.
  • High accuracy, high precision optical/electronic measurements that dig deeper into basic theories and models.
  • Femtosecond optical frequency combs and optical synthesis, ultrafast timing and “time” transfer.
  • Applications of lasers and atomic sensors to real-world problems such as environmental monitoring, energy, navigation and communication systems.
  • Combining diode lasers, atomic vapors, mini-micro-fabrication methods, MEMS, and semiconductor devices for compact atomic devices and sensors.
  • Integration of atoms, lasers, and electronics for enhanced space-time measurements, and exploring the advantages, limitations and applications to navigation and beyond.