Atomic Physics Seminars |
Events During the Week of January 29th through February 5th, 2023
Monday, January 30th, 2023
- Where is All the Antimatter? Electron EDM Search in Cold Molecules Edges Closer
- Time: 11:00 am - 12:00 pm
- Place: 5310 Chamberlin Hall
- Speaker: Xing Wu, Harvard University
- Abstract: The Standard Model of particle physics accurately describes all fundamental particles discovered so far. However, it is unable to address two great mysteries in physics, the nature of dark matter and why matter dominates over antimatter throughout the Universe. Novel theories beyond the Standard Model, such as models that incorporate supersymmetry, may explain these phenomena. These models predict very massive particles whose interactions violate time-reversal (T) symmetry and would give rise to an electric dipole moment (EDM) along the electron’s spin. Thus, searching for EDM provides a powerful probe to these new physics and sheds light on the mystery of the matter-antimatter asymmetry of the Universe.
Here, I share with you the exciting journey of the ACME electron EDM search that has set the recent best limit on the value of electron EDM, measured by spin precession in a superposition of quantum states in cold molecules. This result severely constrains T-violating new physics in 330 TeV energy range, exceeding what can be reached at the Large Hadron Collider. New upgrades employing various quantum control and AMO techniques are now underway, projecting over an order of magnitude sensitivity enhancement ffor the next EDM search.
- Host: Thad Walker
Tuesday, January 31st, 2023
- No events scheduled
Wednesday, February 1st, 2023
- Superradiance in ordered atomic arrays
- Time: 11:00 am - 12:00 pm
- Place: 5310 Chamberlin Hall
- Speaker: Stuart Masson , Columbia University
- Abstract: Collective phenomenona are found in every branch of science; the behavior of the whole differs strongly from the behavior of the individual elements. In quantum optics, a hallmark example is Dicke superradiance. Here, a fully inverted ensemble of atoms emits a short and bright light pulse, known as the superradiant burst, that initially grows in intensity. This is in stark contrast to independent atoms which decay exponentially, emitting a pulse that monotonically decreases in time. Experiments in dense disordered systems have observed the superradiant burst, but there, inhomogeneous broadening plays a large role, making the systems hard to model or control. In contrast, ordered arrays have much lower inhomogeneity - atoms in the bulk all see the same set of neighbors - making them an ideal platform to study dissipative many-body physics. Here, we show the conditions under which such systems produce a superradiant burst. We go beyond two-level approximations, and demonstrate that long-wavelength transitions from ytterbium and strontium atoms can be used to observe such physics. Our work represents an important step in harnessing such systems to build quantum optical sources and as dissipative generators of entanglement.
- Host: Thad Walker
Thursday, February 2nd, 2023
- No events scheduled
Friday, February 3rd, 2023
- No events scheduled