Femtosecond laser pulse surface structuring methods and materials resulting therefrom

Abstract

Embodiments of the present invention are generally directed to materials processing methods using femtosecond duration laser pulses, and to the altered materials obtained by such methods. The resulting nanostructured (with or without macro- and micro-structuring) materials have a variety of applications, including, for example, aesthetic applications for jewelry or ornamentation; biomedical applications related to biocompatibility; catalysis applications; and modification of, for example, the optical and hydrophilic properties of materials including selective coloring.

1 - 20 . (canceled) 
     
     
         21 . An object comprising:
 a metal or metal alloy having a surface with a femtosecond laser treated region;   the surface having a pre-laser treatment profile defining an inward orientation facing into the object and an outward orientation facing away from the object;   the metal or metal alloy having a first light absorption when profiled per the pre-laser treatment profile;   the femtosecond laser treated region of the surface comprising a plurality of nanoscale structure shapes formed by the metal or metal alloy, the nanoscale structure shapes including:   a plurality of nanoscale cavities extending inwardly into the pre-laser treatment profile; and   a plurality of nanoscale protrusions extending outwardly away from the pre-laser treatment profile;   the nanoscale structure shapes increasing absorption of at least some light wavelengths of the metal or metal alloy within the femtosecond laser treated region so that the metal or metal alloy within the femtosecond laser treated region has a second light absorption greater than the first light absorption.   
     
     
         22 . The object of  claim 21 , wherein at least some of the nanoscale protrusions are each adjacent one of the nanoscale cavities. 
     
     
         23 . The object of  claim 22 , further comprising a plurality of nanoscale rims, wherein at least some of the nanoscale rims are each around one of the nanoscale cavities. 
     
     
         24 . The object of  claim 22 , wherein at least some of the nanoscale protrusions include nanoscale spherical structures. 
     
     
         25 . The object of  claim 21 , wherein at least some of the nanoscale cavities are nanoscale pores having a diameter in the range of 40-100 nm. 
     
     
         26 . The object of  claim 21 , wherein at least some of the nanoscale protrusions have a diameter in the range of 20-70 nm and a length of 20-80 nm. 
     
     
         27 . The object of  claim 21 , wherein the nanoscale structure shapes are configured to increase the metal or metal alloy's absorption of substantially all visible light wavelengths to give the metal or metal alloy a black or grey appearance. 
     
     
         28 . The object of  claim 21 , wherein the nanoscale structure shapes are configured to increase the metal or metal alloy's absorption of some visible light wavelengths to give the metal or metal alloy a colored appearance. 
     
     
         29 . The object of  claim 28 , wherein the colored appearance is the same at different viewing angles. 
     
     
         30 . The object of  claim 21 , wherein the nanoscale structure shapes are configured to increase the metal or metal alloy's absorption of some infrared electromagnetic wavelengths. 
     
     
         31 . The object of  claim 21 , wherein the nanoscale structure shapes are configured to increase the metal or metal alloy's absorption of some ultraviolet electromagnetic wavelengths. 
     
     
         32 . The object of  claim 21 , wherein the nanoscale structure shapes are randomly distributed relative to the treated region. 
     
     
         33 . The object of  claim 32 , wherein the treated region further comprises microscale structure shapes. 
     
     
         34 . The object of  claim 33 , wherein the microscale structure shapes comprise a plurality of at least one of micropores, microgrooves, and microchannels. 
     
     
         35 . An object comprising:
 a metal or metal alloy having a surface with a femtosecond laser treated region;   the surface having a pre-laser treatment profile;   the metal or metal alloy having a first light absorption when profiled per the pre-laser treatment profile;   the femtosecond laser treated region of the surface comprising a periodic structure including a plurality of grooves and a plurality of ridges, the treated region further comprising a plurality of nanoscale structure shapes associated with the plurality of grooves and ridges;   the grooves, ridges and structure shapes increasing absorption of at least some light wavelengths of the metal or metal alloy within the femtosecond laser treated region so that the metal or metal alloy within the femtosecond laser treated region has a second light absorption greater than the first light absorption.   
     
     
         36 . The object of  claim 35 , wherein at least some of the nanoscale structure shapes comprise nanoscale protrusions extending outwardly from the grooves and ridges. 
     
     
         37 . The object of  claim 36 , wherein the nanoscale protrusions cover the grooves and ridges. 
     
     
         38 . The object of  claim 36 , wherein at least some of the nanoscale protrusions comprise nanoscale branches supporting nanoscale spherical structures. 
     
     
         39 . The object of  claim 35 , wherein the grooves, ridges and structure shapes are configured to increase the metal or metal alloy's absorption of some visible light wavelengths to give the metal or metal alloy a colored appearance. 
     
     
         40 . The object of  claim 39 , wherein the colored appearance is different at different viewing angles. 
     
     
         41 . A metal or metal alloy object, comprising: a base metal or metal alloy having at least one femtosecond laser treated surface portion, the treated surface portion comprising a plurality of nanoscale structures including nanoscale cavities extending into the surface portion and nanoscale protrusions extending out of the surface portion, wherein the nanoscale structures are configured to decrease the metal or metal alloy's absorption of at least some light wavelengths, the decrease being relative to the same metal or metal alloy without the nanoscale structures. 
     
     
         42 . A metal or metal alloy object, comprising: a base metal or metal alloy having at least one femtosecond laser treated surface portion, the treated surface portion comprising a plurality of nanoscale structures including nanoscale cavities extending into the surface portion and nanoscale rims extending out of the surface portion and around at least some of the nanoscale cavities, wherein the nanoscale structures are configured to decrease the metal or metal alloy's absorption of at least some light wavelengths, the decrease being relative to the same metal or metal alloy without the nanoscale structures.