Cryostat for studying samples in a vacuum

Abstract

Cryostat ( 1 ) for studying samples in a vacuum, which cryostat comprises a cold finger ( 2 ) equipped with a finger portion as well as a base portion ( 10 ) rigidly connected to the finger portion, which cryostat also includes a sample support ( 32 ) mounted on a free end for cooling of the finger portion, wherein this finger portion is placed in a vacuum chamber ( 4 ). The vacuum chamber is partially defined by a one-piece hollow part ( 6 ) defining an open cavity ( 46 ) with a single opening ( 44 ) through which the finger portion passes, and the sample support is located inside said open cavity ( 46 ). The chamber is also defined by a cryostat body ( 8 ) of which an external cylindrical surface with a circular cross-section ( 36 ) cooperates with a rotation device ( 62 ).

1 . Cryostat ( 1 ) for studying samples in a vacuum using electromagnetic radiation, said cryostat comprising a cold finger ( 2 ) equipped with a finger portion ( 14 ) as well as a base portion ( 10 ) rigidly connected to the finger portion ( 14 ) and enabling in particular the arrival of pressurised gas, which cryostat also includes a sample support ( 32 ) mounted on a free end for cooling ( 18 ) of the finger portion ( 14 ), wherein this same finger portion ( 14 ) of the cold finger ( 2 ) is placed in a vacuum chamber ( 4 ), wherein said vacuum chamber ( 4 ) is partially defined by a one-piece hollow part ( 6 ) defining an open cavity ( 46 ) with a single opening ( 44 ) through which the finger portion ( 14 ) passes, and the sample support ( 32 ) is located inside the aforementioned open cavity ( 46 ), characterised in the said vacuum chamber ( 4 ) is also defined by a cryostat body ( 8 ) comprising a through-hole ( 30 ) through which the finger portion ( 14 ) passes, wherein said cryostat body ( 8 ) is connected in a sealed manner to the hollow part ( 6 ) and to the base portion ( 10 ) of the cold finger ( 2 ), and in that the cryostat is also equipped with a rotation device ( 62 ) cooperating with an external cylindrical surface with a circular cross-section ( 36 ) of the cryostat body ( 8 ). 
     
     
         2 . Cryostat ( 1 ) according to  claim 1 , characterised in that said hollow part ( 6 ) is securely assembled to an attachment flange ( 50 ) mounted on said cryostat body ( 8 ). 
     
     
         3 . Cryostat ( 1 ) according to  claim 2 , characterised in the said hollow part ( 6 ) is assembled securely to the attachment flange ( 50 ) by gluing, and in that the latter is mounted on said cryostat body ( 8 ) by screwing. 
     
     
         4 . Cryostat ( 1 ) according to  claim 1 , characterised in that said cryostat body ( 8 ) is mounted on said base portion ( 10 ) of the cold finger ( 2 ) by screwing. 
     
     
         5 . Cryostat ( 1 ) according to  claim 1 , characterised in that said cryostat body ( 8 ) comprises a hole ( 34 ) allowing for the vacuum drawing of said chamber ( 4 ). 
     
     
         6 . Cryostat ( 1 ) according to  claim 1 , characterised in that said hollow part ( 6 ) has a tube shape closed off at one of its two ends. 
     
     
         7 . Cryostat ( 1 ) according to  claim 6 , characterised in that said hollow part ( 6 ) has a tube shape with a circular cross-section. 
     
     
         8 . Cryostat ( 1 ) according to  claim 6 , characterised in that said hollow part ( 6 ) has a tube shape with a substantially square cross-section. 
     
     
         9 . Cryostat ( 1 ) according to  claim 1 , characterised in that it is designed so as to maintain a sample located in said chamber ( 4 ) at a temperature of around 80° K, and in a secondary vacuum. 
     
     
         10 . Cryostat ( 1 ) according to  claim 1 , characterised in that said hollow part ( 6 ) defining the open cavity ( 46 ) is made of quartz. 
     
     
         11 . Cryostat ( 1 ) according to  claim 1 , characterised in that said sample support ( 32 ) has a through-hole ( 32   b ) intended to be covered by the sample. 
     
     
         12 . Cryostat ( 1 ) according to  claim 1 , characterised in that said finger portion ( 14 ) has the form of a straight glass slide in which a coil ( 17 ) is etched, enabling the expansion of the pressurised gas through a series of diaphrams. 
     
     
         13 . Assembly for studying samples in a vacuum, characterised in that it includes a source of electromagnetic radiation, as well as a cryostat ( 1 ) according to any one of the previous claims.