“SmCo” is short-hand for Samarium Cobalt, a type of permanent magnet material. Good general descriptions of Samarium Cobalt material are available at:

• https://cdn2.hubspot.net/hubfs/4788906/Electronenergy_December2018/Docs/EEC-SmCo-Sheet.pdf
• https://www.buntingeurope.com/wp-content/uploads/2018/07/BME_Samarium_Cobalt_data_sheet.pdf
• http://www.allmagnetics.com/smco.htm
• http://www.magnetsales.com/smco/Smco1.htm
• http://en.wikipedia.org/wiki/Samarium-cobalt_magnet
• SmCoProperties