{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T17:18:03Z","timestamp":1778779083296,"version":"3.51.4"},"reference-count":35,"publisher":"IOP Publishing","issue":"4","license":[{"start":{"date-parts":[[2021,2,11]],"date-time":"2021-02-11T00:00:00Z","timestamp":1613001600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/iop-standard\/v1"},{"start":{"date-parts":[[2021,2,11]],"date-time":"2021-02-11T00:00:00Z","timestamp":1613001600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"name":"NIH","award":["5R01EB02390302"],"award-info":[{"award-number":["5R01EB02390302"]}]},{"DOI":"10.13039\/100010865","name":"Stanford Engineering","doi-asserted-by":"crossref","award":["Stanford Graduate Fellowship in Science & Engineer"],"award-info":[{"award-number":["Stanford Graduate Fellowship in Science & Engineer"]}],"id":[{"id":"10.13039\/100010865","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100006132","name":"Office of Science","doi-asserted-by":"crossref","award":["DE-AC02-76SF00515"],"award-info":[{"award-number":["DE-AC02-76SF00515"]}],"id":[{"id":"10.13039\/100006132","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Phys. Med. Biol."],"published-print":{"date-parts":[[2021,2,21]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    In this work, we continue our study of a new method for the detection of ionizing radiation with the potential for a dramatic improvement in coincidence time resolution (CTR) for time-of-flight positron emission tomography (ToF-PET) using the modulation of a material\u2019s optical properties instead of the scintillation mechanism. Our previous work has shown that for non-scintillation materials such as bismuth silicon oxide (BSO) and cadmium telluride (CdTe), their refractive index can be modulated by annihilation photon interactions. The ultrafast nature of this process however remains unexplored. The ionizing radiation-induced charge carriers alter the local band structure in these materials, thus changing the complex refractive index. This mechanism is routinely used at the linac coherent light source (LCLS) facility of the SLAC National Accelerator Laboratory to measure x-ray pulse arrival times with femtosecond scale resolution for photon energies between 0.5 and 10 keV. The method described here follows that example by using a frequency chirped visible continuum pulse to provide a monotonic wavelength-to-time mapping by which one can measure the time-dependent refractive index modulation. In addition, we describe an interference-based measurement setup that allows for significantly improved sensitivity while preserving a timing precision of approximately 10 fs (\n                    <jats:italic>\u03c3<\/jats:italic>\n                    ) when measuring the arrival time of below 10 keV x-ray pulses with yttrium aluminum garnet (YAG) crystal. The method is presented in the context of ToF-PET application with further discussions on the potential CTR achievable if a similar detection concept is adopted for detecting 511 keV photons. Semi-empirical analysis indicates that the predicted CTR achievable is on the order of 1 ps (FWHM).\n                  <\/jats:p>","DOI":"10.1088\/1361-6560\/abd951","type":"journal-article","created":{"date-parts":[[2021,1,8]],"date-time":"2021-01-08T06:53:17Z","timestamp":1610088797000},"page":"045032","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":12,"title":["Ionizing photon interactions modulate the optical properties of crystals with femtosecond scale temporal resolution"],"prefix":"10.1088","volume":"66","author":[{"given":"Li","family":"Tao","sequence":"first","affiliation":[{"name":"Stanford University"},{"name":"Stanford University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ryan N","family":"Coffee","sequence":"additional","affiliation":[{"name":"SLAC National Accelerator Laboratory"},{"name":"The PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diana","family":"Jeong","sequence":"additional","affiliation":[{"name":"Stanford University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Craig S","family":"Levin","sequence":"additional","affiliation":[{"name":"Stanford University"},{"name":"Stanford University"},{"name":"Stanford University"},{"name":"Stanford University"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"266","published-online":{"date-parts":[[2021,2,11]]},"reference":[{"key":"pmbabd951bib1","doi-asserted-by":"publisher","first-page":"4250","DOI":"10.1103\/PhysRevLett.76.4250","type":"journal-article","article-title":"Ultrafast spin dynamics in ferromagnetic nickel","volume":"76","author":"Beaurepaire","year":"1996","journal-title":"Phys. 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All rights, including for text and data mining, AI training, and similar technologies, are reserved.","name":"copyright_information","label":"Copyright Information"},{"value":"2020-08-05","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2021-01-07","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2021-02-11","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}