Colloquium

Junior and senior physics majors attend our biweekly colloquium series, held on Tuesday afternoons at 4:30 pm in Shanahan B460. The talks are open to all students and to the public, and are frequently attended by scientists from the other Claremont Colleges, Cal Poly Pomona, and others. The series features speakers from a broad range of institutions and fields of physics.
HMC Physics Colloquium shot
March 22, 2016 Janice Hudgings, Pomona College
Photonic Device Applications of Modulated-Reflectance Imaging

We have demonstrated a high-resolution (250nm, 10mK), non-contact modulated reflectance imaging technique which, in combination with an energy balance model, can be used for spatially resolved thermal, optical, and electrical metrology of optoelectronic devices. Applications include optical testing of photonic integrated circuits, current spreading and thermal management in light emitting diodes, thermal lensing in vertical cavity surface emitting lasers, and ...

March 8, 2016 Jason Hogan (’03), Stanford University
Tests of gravity and quantum mechanics using atom interferometry

Precision atom interferometry is poised to become a powerful tool for discovery in fundamental physics. Towards this end, I will describe recent, record-breaking atom interferometry experiments performed in a 10-meter drop tower that demonstrate long-lived quantum superposition states with macroscopic spatial separations. The potential of this type of sensor is only beginning to be realized, and the ongoing march toward ...

Feb. 23, 2016 Marissa Giustina, Institute for Quantum Optics and Quantum Information — Vienna
Significant-Loophole-Free Test of Local Realism With Entangled Photons

Local realism is the worldview in which physical properties of objects exist independently of measurement and where physical influences cannot travel faster than the speed of light. Bell’s theorem states that this worldview is incompatible with the predictions of quantum mechanics, as is expressed in Bell’s inequalities. Previous experiments convincingly supported the quantum predictions. Yet, every experiment requires assumptions that ...

Feb. 9, 2016 Candidate C, Harvey Mudd College
Games, Electrical Networks, and Quantum Algorithms
Quantum computers exploit the quantum nature of physical systems to perform computations. While we have yet to build a large-scale quantum computer, we can prove that such devices would have an advantage over standard computers for some problems. However, there are still many tasks for which we don't have a good understanding of the performance of quantum computers. For ...
Feb. 2, 2016 Candidate B, Harvey Mudd College
Illuminating the Dark Universe with Particle Colliders

The stars and gases observed in our galaxy and beyond comprise only 15% of the total matter in the universe; the remainder consists of dark matter, so called because it does not emit, reflect, or absorb light. Because the identity of dark matter and the forces it experiences are currently unknown, discovering the physics behind it remains one of the ...

Jan. 26, 2016 Candidate A, Harvey Mudd College
Multi-Scale Studies of the Physics of Earthquakes

Earthquake faults are complex systems that span a huge range of length and time scales. These scale-rich systems are challenging to model, as each scale is itself a complex system that depends on the dynamics occurring at the other scales. Because the largest, damaging earthquakes are rare, estimates of risk based on historical event occurrence is highly uncertain, and physics-based ...

Dec. 8, 2015 Andrew Wetzel (’05), Caltech
Simulating the Universe, one galaxy at a time

Within the cosmic web, galaxies form as baryonic gas flows along cosmic filaments into dark-matter halos. This gas fuels the formation of stars within galaxies, while the resultant feedback from stars and supernovae drive strong outflows of gas from galaxies. Understanding the physics of this complex interplay between cosmic inflows and feedback-driven outflows is one of the most significant questions ...

Oct. 27, 2015 Michael J. Martin (’06), Caltech
Nanophotonics and ultracold atoms: a new set of tools for controlling atom-light interactions

Nano- and micro-scale optical systems, with feature sizes comparable to the wavelength of light, represent a powerful way to control the properties of optical fields. For example, photonic crystals (periodically patterned dielectrics) possess optical properties linked to their underlying geometry that can significantly depart from those of the dielectric material from which they are patterned. In the field of quantum ...

Oct. 6, 2015 John Belcher, Massachusetts Institute of Technology
Voyager 1 in the Interstellar Medium: What are we Seeing Out There?

The Voyager spacecraft were launched in the Fall of 1977, 38 years ago. After a “grand tour” of the outer planets, ending with Voyager 2 at Neptune in 1989, the spacecraft have continued outward toward interstellar space, continuing to return data about the particle and field environment of the distant solar and interstellar medium. Voyager 1 is farthest from the ...

Sept. 22, 2015 HMC Physics Majors, Harvey Mudd College
Off-campus summer research in physics

The following students will describe how they identified summer research positions, what they worked on, and what their REU program was like beyond the particular project they worked on:

  • Matthew Dannenberg
  • Sabine Fontaine
  • Nathaniel Leslie
  • Morgan Mastrovich
  • Colin Okasaki
  • Jonathan Ueki
  • Shanel Wu
April 28, 2015 Jim Enstrom (’65), University of California at Los Angeles
This talk has been cancelled

I will describe how I have used my 1965 HMC B.S. in physics to rise, at least briefly, to the top of two vastly different branches of science: first, a very hard science—experimental elementary particle physics at Stanford University, and second, a very soft science—environmental epidemiology at UCLA.

My talk will explain the important roles that HMC, creative thinking, ...

April 14, 2015 Katharina Gillen, Cal Poly Pomona
Quantum Computing With a 2D Array of Movable Atom Traps Formed by Pinholes

Quantum computers have the potential to perform certain tasks much faster than even the most powerful supercomputers through the use of superposition and entanglement, two of the unusual features of quantum mechanics. Despite the fact that many different systems are being explored as candidates, no fully functioning quantum computer has been built yet. One approach is quantum computing using (neutral) ...

March 31, 2015 Emma Wollman, Caltech
Evidence of quantum squeezing of motion in a mechanical resonator

Quantum mechanics places limits on the minimum energy of a harmonic oscillator via the ever-present “zero-point” fluctuations of the quantum ground state. Through squeezing, however, it is possible to decrease the noise of a single motional quadrature below the zero-point level as long as noise is added to the orthogonal quadrature. While squeezing below the quantum noise level was achieved ...

March 10, 2015 Jason Rhodes (’94), Jet Propulsion Laboratory
Exploring the Dark Sector with Euclid and WFIRST

The past decade has seen the emergence of the so-called “concordance model” of cosmology. In this model, the Universe started about 13.7 billion years ago in a Big Bang and is now dominated by dark matter and dark energy. Together this poorly understood “dark sector” makes up about 95% of the Universe, but the nature of these phenomena remains elusive. ...

March 3, 2015 Jason Gallicchio, University of Chicago
A Long Winter: Cosmic Microwave Background Polarization with the South Pole Telescope

The South Pole Telescope is the largest Cosmic Microwave Background telescope in the world. Its high-resolution maps were the first to show evidence of so-called B-mode polarization due to gravitational lensing by intervening matter. Wider maps are now shedding light on the larger-sized B-modes generated by gravity waves created a right after the big bang. I will discuss the technology ...