University of Colorado Boulder

<p><strong>Overview:</strong></p>
<p>As one of 34 U.S. public research institutions belonging to the prestigious Association of American Universities (AAU)—and the only member in the Rocky Mountain region—University of Colorado Boulder’s (CU Boulder) goal is to directly affect Colorado communities through collaborative research, innovation and entrepreneurship. At CU Boulder, students, faculty and staff are provided with the tools they need to create a community of thinkers and doers who can benefit humanity locally, nationally and abroad.</p>
<p><strong>Research:</strong></p>
<p>Research at CU Boulder encompasses thousands of scholarly, scientific and creative endeavors at any given time, resulting in new knowledge, technologies and creative work that advance the economy, culture and health of Colorado, the nation and the world.</p>
<p>The Research &amp; Innovation Office is focused on creating impact by cultivating and supporting collaboration, transformation and leadership. At the heart of this focus are the diverse contributions of a wide range of world-class experts—working together in new and innovative ways to accelerate ideas through the entire innovation lifecycle, from idea to impact.</p>
<p><strong>Industry Partnerships:</strong></p>
<p>Ranked as one of the nation’s top 20 entrepreneurial universities and the #2 most innovative tech hub in the U.S., CU Boulder has granted 140 license and option agreements to businesses in the past five years from CU Boulder discoveries.</p>
<p>With expertise in patents, copyrights and licensing, the CU Boulder Tech Transfer Office helps translate discovery into impact through transparent, flexible, best practice intellectual property management services, and connect campus researchers with a variety of commercialization programs in the university and the community. </p>


<h1 id="background">Background</h1>
<p>The extremely high sensitivities of zero-field magnetometers (ZFM) have paved the way towards new applications such as non-cryogenic magnetocardiography (MCG) and magnetoencephalography (MEG). In the last several years, progress has been made towards improving the sensitivity of total-field magnetometers (TFM) that operate in unshielded (Earth’s) magnetic field environment. Their sensitivity is typically lower than that of the ZFM. The TFM offers higher dynamic range and relaxed control of the ambient magnetic fields, and thus can be used in applications incompatible with zero-field operation, such as ultralow-field NMR and magnetic anomaly detection. TFM reach highest sensitivity when they measure the precession of an atomic polarization in a plane perpendicular to the direction of the measured ambient magnetic field. The preparation of the atomic polarization in such a plane difficult, as the ambient magnetic field counteracts the spin preparation done using optical pumping.</p>
<h1 id="technology-overview">Technology Overview</h1>
<p>Researchers at the University of Colorado have come up with a new method to increase the efficiency of the atomic polarization preparation by zeroing the ambient magnetic field at the position of a pulsed TFM. Specifically, the existing ambient magnetic field is nulled at the position of the TFM during the preparation phase of the atomic polarization. This is achieved by applying a DC magnetic field in the opposite direction to the ambient one during the preparation of the atomic polarization. The field zeroing increases the efficiency of the atomic polarization preparation through optical pumping.</p>
<p>Additionally, it is known that the free precession of the atomic polarization reacts instantaneously to changes of the ambient magnetic field. This means that the bandwidth of the ambient magnetic field measurement is not limited by the repetition rate of the TFM pump-probe cycle, which is determined by the sum of the pump and probe phase durations. A TFM that uses a pump-probe cycle can thus measure ambient magnetic field dynamics that is faster than the TFM repetition rate. The sensitivity with which the ambient field dynamics is measured is given by the single-cycle sensitivity of the TFM, while the bandwidth exceeds significantly the TFM repetition rate.</p>
<h3 id="-stage-of-development-"><strong>Stage of Development</strong></h3>
<p>Technology Readiness Level (TRL): 7.</p>
<h1 id="benefits">Benefits</h1>
<ul>
<li>Higher TFM sensitivity</li>
<li>Polarization preparation not dependent on ambient magnetic field</li>
<li>Can be optimized to achieve maximum atomic polarization</li>
<li>No need for short-pulse, high-power pumping light, resonant AC or strong DC magnetic field pulses</li>
</ul>
<h1 id="applications">Applications</h1>
<ul>
<li>Magnetoencephalography</li>
<li>Magnetocardiography</li>
<li>Ultralow-field nuclear magnetic resonance</li>
<li>Magnetic Anomaly Detection, Magnetorelaxometry</li>
</ul>
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