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Christian Lange named Purdue Innovates Commercialization Fellow

Congratulations to Christian Lange on being named a Purdue Innovates Commercialization Fellow.

New Paper: Cavity QED with Molecular Emitters in ACS Nano

Our latest paper led by Christian Lange has been published in ACS Nano! We present a hybrid solid-state cavity quantum electrodynamics platform that integrates coherent organic molecules with high-quality-factor silicon nitride photonic crystal cavities. By mechanically transferring thin anthracene crystals doped with dibenzoterrylene (DBT) onto prefabricated cavities, we preserve both the cavity quality and molecular coherence. With up to ten molecules coupled to a single cavity, we observe cav

New Paper: First Order Maxwell Operator Formalism for Macroscopic QED

We have a new preprint presenting a first-order electromagnetic operator formalism for macroscopic quantum electrodynamics. This work by Ishita Agarwal introduces a compact first-order Maxwell operator approach that simplifies the treatment of quantized electromagnetic fields in the presence of dispersive and absorbing dielectric media. The formalism provides a natural framework for field decomposition and mode analysis in complex nanophotonic geometries.I Agarwal, A Kundu, CM Lange, JD Hood, "F

New Paper: Vapor Phase Assembly of Molecular Emitter Crystals for Photonic Integrated Circuits

We are excited to share our latest preprint on the vapor-phase assembly of molecular emitter crystals for photonic integrated circuits. In this work, we demonstrate a scalable method for growing optically thin, high emitter density anthracene crystals doped with dibenzoterrylene (DBT) molecules directly onto photonic chips. This approach enables the deterministic integration of quantum emitters with nanophotonic structures, a key step toward building practical quantum photonic devices.AD Keni, C

Congratulations Emma and Team: New Review in Nature Reviews Materials

Congratulations to Emma Daggett and the entire team! Our review article on many-body entanglement in solid-state quantum emitters has been published in Nature Reviews Materials. Led by Emma Daggett, this comprehensive review covers the path toward achieving many-body entanglement with solid-state quantum emitters integrated in nanophotonic structures. We discuss single-emitter coherence and control, photon-mediated interactions, and the outlook for scalable quantum networks based on these platfo

Quadrupole imaging and cooling paper

We demonstrated background-free imaging and single-photon sideband cooling for a single Cs atom trapped in an optical tweezer. This is a significant advancement in neutral-alkali atoms, as previously there weren't any narrow lines used for imaging/cooling. This paper also discusses how one can drive quadrupole transitions transferring two units of angular momentum using a single photon by either a focused Gaussian beam or a vortex beam generated via an SLM. Here's the link to the arXiv article:

Cooling theory paper now on arXiv

[2406.19153] A Generalized Theory for Optical Cooling of a Trapped Atom with Spin (arxiv.org)

Accepted to Nature Physics

New quantum optics paper out in Nature Physics!Superradiant and subradiant states in lifetime-limited organic molecules through laser-induced tuning | Nature Physics

New quantum optics paper on arXiv

[2308.08037] Superradiant and subradiant states in lifetime-limited organic molecules through laser-induced tuning

Building ultrastable cavity housing

Karl and Claire are building a new vacuum chamber to house an ultra-stable cavity for locking a laser to the Cs 5D transition.

New paper on arXiv

[2305.02405] Imaging a $^6$Li Atom In An Optical Tweezer 2000 Times with $Λ$-Enhanced Gray Molasses (arxiv.org)

Two Photon Peak

Experimental observation of the doubly-excited state of two coupled dibenzoterrylene molecules.

First Successful G2

We observed single-emitter behavior in the autocorrelation function of a Dibenzoterrylene molecule!

First Signal from Nanophotonic Cavity

We observed our first resonance from our nanobeam cavity, with an estimated quality factor of Q = 7000

First Narrow Linewidths for Quantum Optics

Observed narrow linewidth of Dibenzoterrylene embedded in an anthracene matrix in our new Montana cryostat (60 MHz)

Fabricated first nanobeam cavity

We fabricated a silicon nitride photonic crystal cavity with grating coupler to interact with the organic molecules.

Lithium gray molasses cooling

First Lithium MOT

MOVED INTO RENOVATED LAB!

We move into our renovated lab in the basement of Brown.

Pump down Li + Cs vacuum chamber

Cs Rabi oscillations

With use a Raman transition to drive the Cs atoms between two ground state hyperfine states.

Cs loading rate measurement in an array of tweezers

Optimized imaging for Cs and trapped in 2x2 array.

Single Cs atom trapped in tweezer

We have trapped a single Cs atom in an optical tweezer. The micron-size optical tweezer picks out a single atom from the magneto-optical trap. The flickering is the atom coming into the trap, and then being kicked out by collisions with the background gas.

Polarization gradient cooling is successfully done for Cs MOT

Demonstrated PG cooling of a Cs MOT to decrease the temperature from 100uK down to 10 uK.

First magneto-optical trap

We created a cesium magneto-optical trap. The white dot in the center of the glass cell is a cloud of 105 cesium atoms at a temperature of 200µK. The cesium atoms are trapped by 6 laser beams and a magnetic field gradient inside an ultrahigh vacuum chamber glass cell (10-10 Torr). The magnetic field gradient is made by the orange coils in the right picture.

Pumping down Cesium vacuum chamber

Assembling, baking, and pumping the vacuum chamber down to ultrahigh vacuum (<10-10 Torr).

Cesium lasers are locked

Using cesium saturation absorption spectroscopy to lock a diode laser to the cesium transition. The laser will be used for the magneto-optical trap.