Journal of large-scale research facilities, 2, A48 (2016) http://dx.doi.org/10.17815/jlsrf-2-73 Published: 19.02.2016 The PM3 beamline at BESSY II Helmholtz-Zentrum Berlin für Materialien und Energie * Instrument Scientists: - Dr. Torsten Kachel, Helmholtz-Zentrum Berlin für Materialien und Energie, phone: +49 30 8062-12942, email: torsten.kachel@helmholtz-berlin.de Abstract: PM3 merges the developments of the former BESSY I SX700 III monochromator for ellipti- cally polarized VUV radiation and of BESSY II collimated plane grating monochromators. This way it is possible to achieve circular polarization from a BESSY II dipole in the range 20 - 2000 eV with high photon �ux, high energy resolution and high stability. 1 Introduction PM3 is designed to deliver synchrotron radiation of variable polarization (linear and left- or right- handed elliptical), easily tuneable over a wide range of photon energies. Operating in the soft X-ray range, the major part of beamtime is dedicated to the investigation of magnetic materials using magnetic circular dichroism (XMCD) techniques. It is an "open port" beamline meaning that it is not equipped with a permanent experimental station. Rather, varying user experiments are connected to the PM3 beamline according to the beamtime schedule. At BESSY II PM3 has been installed in 2001. The ac- cessible photon energies range from about 30 to 2000 eV. The energy resolution of 33,000 @ 64 eV is the best reported for any SX700 type monochromator so far. A signal-to-noise ratio close to the shot noise level, fast "on-the- �y" scanning and horizontal beam position control make PM3 one of the most productive dipole beamlines at BESSY II. The high performance of the beamline is re�ected by selected publications: Antoniak et al. (2011); Luo et al. (2012); Manzke et al. (2012); Radu et al. (2012); Sanyal et al. (2010); Valencia et al. (2011). *Cite article as: Helmholtz-Zentrum Berlin für Materialien und Energie. (2016). The PM3 beamline at BESSY II. Journal of large-scale research facilities, 2, A48. http://dx.doi.org/10.17815/jlsrf-2-73 1 http://jlsrf.org/ http://dx.doi.org/10.17815/jlsrf-2-73 http://dx.doi.org/10.17815/jlsrf-2-73 https://creativecommons.org/licenses/by/4.0/ Journal of large-scale research facilities, 2, A48 (2016) http://dx.doi.org/10.17815/jlsrf-2-73 Figure 1: View of beamline PM3 (with user experiment chamber ALICE). 2 Instrument application Typical applications are: • Sub-Monolayers to Multilayers (inorganic or organic) • Liquids • Ferrimagnets • Exchange Bias systems • Multiferoics • Magnetic Nanoparticles 3 Source The source is the dipole D111. 4 Optical design From the layout it is seen that the design is close to the one of a standard BESSY PGM. A refocusing mirror is not implemented. The focusing is astigmatic. The vertical focus is located in the exit slit plane at 25500 mm. The horizontal focus lies at 26000 mm. The smallest spot size is observed at 25850 mm. The beam divergences are 2.68 mrad (hor.) and 1.17 mrad (vert. @ β = 4°). The applicability of elliptical polarization is mainly given and determined by the rotation of M1 around the light axis. This principle is described in detail in Kachel et al. (2015). 2 http://dx.doi.org/10.17815/jlsrf-2-73 https://creativecommons.org/licenses/by/4.0/ http://dx.doi.org/10.17815/jlsrf-2-73 Journal of large-scale research facilities, 2, A48 (2016) Figure 2: Optical layout of beamline PM3. 5 Technical data Location 12.2 Source D111 Monochromator PM3 Energy range 20 - 1900 eV Energy resolution 32000 at 64 eV Flux 109 - 1010 ph/s Polarization • Horizontal • Circular Divergence horizontal 1.5 mrad Divergence vertical 1 mrad Focus size (hor. x vert.) 180 µm x 100 µm Distance focus/last valve 350 mm Height focus/�oor level 1432 mm Free photon beam available Yes Fixed end station No Table 1: Technical parameters of beamline PM3. References Antoniak, C., Gruner, M. E., Spasova, M., Trunova, A. V., Römer, F. M., Warland, A., . . . Wende, H. (2011). A guideline for atomistic design and understanding of ultrahard nanomagnets. Nature Com- munications, 2, 528. http://dx.doi.org/10.1038/ncomms1538 Kachel, T., Eggenstein, F., & Follath, R. (2015). A soft X-ray plane-grating monochromator optimized for elliptical dipole radiation from modern sources. Journal of Synchrotron Radiation, 22(5), 1301–1305. http://dx.doi.org/10.1107/S1600577515010826 3 http://dx.doi.org/10.17815/jlsrf-2-73 http://dx.doi.org/10.1038/ncomms1538 http://dx.doi.org/10.1107/S1600577515010826 https://creativecommons.org/licenses/by/4.0/ Journal of large-scale research facilities, 2, A48 (2016) http://dx.doi.org/10.17815/jlsrf-2-73 Luo, Y., Bernien, M., Krüger, A., Hermanns, C. F., Miguel, J., Chang, Y.-M., . . . Haag, R. (2012). In situ hydrolysis of imine derivatives on au(111) for the formation of aromatic mixed self-assembled monolayers: Multitechnique analysis of this tunable surface modi�cation. Langmuir, 28(1), 358-366. http://dx.doi.org/10.1021/la202696a Manzke, A., Plettl, A., Wiedwald, U., Han, L., Ziemann, P., Schreiber, E., . . . Kaiser, U. (2012). Formation of highly ordered alloy nanoparticles based on precursor-�lled latex spheres. Chemistry of Materials, 24(6), 1048-1054. http://dx.doi.org/10.1021/cm203241p Radu, F., Abrudan, R., Radu, I., Schmitz, D., & Zabel, H. (2012). Perpendicular exchange bias in ferri- magnetic spin valves. Nature Communications, 3, 715. http://dx.doi.org/10.1038/ncomms1728 Sanyal, B., Antoniak, C., Burkert, T., Krumme, B., Warland, A., Stromberg, F., . . . Eriksson, O. (2010). Forcing ferromagnetic coupling between rare-earth-metal and 3d ferromagnetic �lms. Physical Re- view Letters, 104, 156402. http://dx.doi.org/10.1103/PhysRevLett.104.156402 Valencia, S., Crassous, A., Bocher, L., Garcia, V., Moya, X., Cheri�, R. O., . . . Bibes, M. (2011). Interface-induced room-temperature multiferroicity in batio3. Nature Materials, 10, 753-758. http://dx.doi.org/10.1038/nmat3098 4 http://dx.doi.org/10.17815/jlsrf-2-73 http://dx.doi.org/10.1021/la202696a http://dx.doi.org/10.1021/cm203241p http://dx.doi.org/10.1038/ncomms1728 http://dx.doi.org/10.1103/PhysRevLett.104.156402 http://dx.doi.org/10.1038/nmat3098 https://creativecommons.org/licenses/by/4.0/ Introduction Instrument application Source Optical design Technical data