Sarvjit D. Shastri

After receiving a B.S. from Caltech, Sarvjit Shastri obtained a Ph.D. in applied physics from Cornell University in 1994 for synchrotron radiation research on x-ray polarization optics and nuclear resonant scattering, conducted at CHESS (Cornell) and NSLS (Brookhaven). Since then, he has been at Argonne​’s APS, developing high-energy (50–150 keV) x-ray optics and scattering methods. Shastri has also worked on optics simulations for short-pulsed x-ray sources such as x-ray free-electron lasers (XFELs). Recently, he has directed a significant part of his time towards leading the APS-Upgrade project’s High-Energy X-Ray Microscope (HEXM) long beamline at Sector 20-ID.

His high-energy optics¹ efforts include: monochromatization (under high-heat-load⁷ and for high-resolution applications⁸), focusing optics,^{2-6, 9-10} and imaging,¹¹ which enable numerous high-energy diffraction microscopy (HEDM) techniques,^19-20 element-specific resonant scattering at heavy-element K-shell ionization thresholds,^14-18 and new coherence-based investigations.^21-22 Shastri’s short-pulse optics work involves early theoretical investigations of effects in dynamical (i.e., perfect crystal) diffraction of femtosecond x-ray pulses,^12-13 such as broadening, shot-to-shot fluctuations, and impulse responses (Green’s functions). Examples of the latter are the temporal scattering profile in Laue crystals, and the thin-crystal Bragg-transmitted wake-field beats of relevance in XFEL self-seeding.

Selected Publications (25 from full list)

High-energy x-ray optics - general

1. S. D. Shastri, ​“High-energy x-ray optics development at the APS and its shaping of the HEXM materials science beamline,” SRI-2024 (invited), J. Phys.: Conf. Ser. 3010, 012055 (2025)

High-energy focusing - diamond refractive optics

2. S. D. Shastri and S. Antipov, ​“Focusing, collimation, and beam expansion of high-energy x-rays with diamond refractive lenses,” J. Synchrotron Rad. 33 (5), accepted (2026)

High-energy focusing - saw-tooth refractive lenses

3. N. Moldovan, B. Matos-Vazquez, A. C. Chuang, and S. D. Shastri, ​“Fabrication of saw-tooth x-ray refractive lenses aberration-corrected by a period gradient,” SPIE 13620, 136200O-1-13 (2025)

4. S. D. Shastri and N. Moldovan, ​“Submicron focusing of high-energy x-rays with silicon saw-tooth refractive lenses: fabrication and aberrations,” Optics Express 28 (24), 36505-36515 (2020)

5. S. D. Shastri, P. Kenesei, A. Mashayekhi, and P. Shade, ​“Focusing with saw-tooth refractive lenses at a high-energy x-ray beamline,” J. Synchrotron Rad. 27, 590-598 (2020)

6. S. D. Shastri, J. Almer, C. Ribbing, and B. Cederstrom, ​“High-energy x-ray optics with silicon saw-tooth refractive lenses,” J. Synchrotron Rad. 14, 204-211 (2007)

First cryogenically-cooled bent-crystal monochromator

7. S. D. Shastri, K. Fezzaa, A. Mashayekhi, W.-K. Lee, P. B. Fernandez, and P. L. Lee, ​“Cryogenically cooled, bent double-Laue monochromator for high-energy undulator x-rays (50-200 keV),” J. Synchrotron Rad. 9, 317-322 (2002)

First high-energy-resolution monochromator at high energies

8. S. D. Shastri, ​“Combining flat crystals, bent crystals, and compound refractive lenses for high-energy x-ray optics,” J. Synchrotron Rad. 11, 150-156 (2004)

First focusing with stacked Fresnel zone plates

9. S. D. Shastri, J. M. Maser, B. Lai, and J. Tys, ​“Microfocusing of 50 keV undulator radiation with two stacked zone plates,” Opt. Commun. 197 (1-3), 9-14 (2001)

Kinoform refractive lenses at high energies

10. S. D. Shastri, K. Evans-Lutterodt, R. L. Sheffield, A. Stein, M. Metzler, and P. Kenesei, ​“Kinoform lens focusing of high-energy x-rays (50--100 keV),” SPIE 9207, 920704-1-9 (2014)

First transmission x-ray microscope at high energies

11. S. D. Shastri, P. Kenesei, and R. M. Suter, ​“Refractive lens based full-field x-ray imaging at 45--50 keV with sub-micron resolution,” SPIE 9592, 95920X-1-9 (2015)

First short-pulse x-ray/FEL simulations in perfect crystals

12. S. D. Shastri, P. Zambianchi, and D. M. Mills, ​“Femtosecond x-ray dynamical diffraction by perfect crystals,” SPIE 4143, 69-77 (2001)

13. S. D. Shastri, P. Zambianchi, and D. M. Mills, ​“Dynamical diffraction of ultrashort x-ray free-electron laser pulses,” J. Synchrotron Rad. 8, 1131-1135 (2001)

High-energy resonant scattering (including first demonstrations)

14.  V. Petkov, A. Zafar, P. Kenesei, and S. D. Shastri, ​“Chemical compression and ferroic orders in La substituted BiFeO₃,” Phys. Rev. Materials 7, 054404-1-8 (2023)

15. V. Petkov, B N. Wanjala, R. Loukrakpam, J. Luo, L. Yang, C.-J. Zhong, and S. D. Shastri, ​“Pt-Au alloying at the nanoscale,”  Nano Lett. 12, 4289-4299 (2012)

16. V. Petkov, S. M. Selbach, M. A. Einarsrud, T. Grande, and S. D. Shastri,” Melting of Bi sublattice in nanosized BiFeO₃ perovskite by resonant x-ray diffraction,” Phys. Rev. Lett. 105, 185501-1-4 (2010)

17. V. Petkov and S. D. Shastri, ​“Element-specific structure of materials with intrinsic disorder by high-energy resonant x-ray diffraction and atomic pair-distribution functions: A study of PtPd nanosized catalysts,” Phys. Rev. B 81, 165428-1-8 (2010)

18.  Y. Zhang, A. P. Wilkinson, P. L. Lee, S. D. Shastri, D. Shu, D.-Y. Chung, and M. G. Kanatzidis, ​“Determining metal ion distributions using resonant scattering at very high-energy K-edges: Bi/Pb in Pb₅Bi₆Se₁₄,” J. Appl. Cryst. 38, 433-441 (2005)

Very-far-field high-energy diffraction microscopy (vff-HEDM)

19. U. Lienert, M. C. Brandes, J. V. Bernier, J. Weiss, S. D. Shastri, M. J. Mills, and M. P. Miller, ​“In situ single-grain peak profile measurements on Ti-7Al during tensile deformation,” Mater. Sci. Eng. A 524, 46-54 (2009)

20. B. Jakobsen, H. F. Poulsen, U. Lienert, J. Almer, S. D. Shastri, H. Sorensen, C. Gundlach, and W. Pantleon, ​“Formation and subdivision of deformation structures during plastic deformation,” Science 312, 889-892 (2006)

Demonstration of coherent diffraction imaging (CDI) at high energies

21. N. Bertaux, M. Allain, J. Weizeorick, J.-S. Park, P. Kenesei, S. D. Shastri, J. Almer, M. J. Highland, S. Maddali, and S. O. Hruszkewycz, ​“Sub-pixel high-resolution imaging of high-energy x-rays inspired by sub-wavelength optical imaging,” Optics Express 29 (22), 35003-35021 (2021)

22. S. Maddali, J. S. Park, H. Sharma, S. D. Shastri, P. Kenesei, J. Almer, R. Harder, M. J. Highland, Y. Nashed, and S. O. Hruszkewycz, ​“High-energy coherent x-ray diffraction microscopy of polycrystal grains: Steps toward a multiscale approach,” Phys. Rev. Applied 14, 024085 (2020)

Sources (insertion devices) for high-energy x-rays

23. Y. Ivanyushenkov, K. Harkay, M. Borland, R. Dejus, J. Dooling, C. Doose, L. Emery, J. Fuerst, J. Gagliano, Q. Hasse, M. Kasa, P. Kenesei, V. Sajaev, K. Schroeder, N. Sereno, S. Shastri, Y. Shiroyanagi, D. Skiadopoulos, M. Smith, X. Sun, E. Trakhtenberg, A. Xiao, A. Zholents, and E. Gluskin, ​“Development and operating experience of a 1.1-m-long superconducting undulator at the Advanced Photon Source,” Phys. Rev. Accel. Beams 20, 100701-1-13 (2017)

24. S. D. Shastri, R. J. Dejus, D. R. Haeffner, ​“Experimental characterization of APS Undulator A at high photon energies (50-200 keV),“J. Synchrotron Rad, 5, 67-71 (1998)

25. S. D. Shastri, R. J. Dejus, D. R. Haeffner, and J. C. Lang, ​“Performance of Advanced Photon Source insertion devices at high photon energies (50-300 keV),” Rev. Sci. Instrum. 67, 3346 (1996)