A finite-element study of sapphire anvils for increased sample volumes

Diamond anvil cells enable over Mbar sample pressures to be generated, but remain unsuitable for many measurements due to the limited sample volume available. Larger sapphire anvils have enabled approximately an order of magnitude increase in sample volume, but fail to reach similar pressures due to the mechanical differences between sapphire and diamond, and the difficulties in containing larger sample volumes under pressure. To understand the origin of these limitations, finite element analyses of large sapphire anvils have been performed and compared with experimental loading data.