Imaging of Interlayer Coupling in van der Waals Heterostructures

Jul 28, 2017 - Department of Energy Engineering and Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil,...
0 downloads 12 Views 5MB Size
Subscriber access provided by BOSTON UNIV

Communication

Imaging of interlayer coupling in van der Waals heterostructures using a bright-field optical microscope Evgeny M. Alexeev, Alessandro Catanzaro, Oleksandr Skrypka, Pramoda Kumar Nayak, Seongjoon Ahn, Sangyeon Pak, Juwon Lee, Jung Inn Sohn, Kostya S. Novoselov, Hyeon Suk Shin, and Alexander I. Tartakovskii Nano Lett., Just Accepted Manuscript • Publication Date (Web): 28 Jul 2017 Downloaded from http://pubs.acs.org on July 28, 2017

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

Nano Letters is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Nano Letters

                         

    ∗ † 

  †      †  

  ‡   ‡   ¶ !" # ¶ ! $  ¶       § % ! & ‡    $ ' &&∗ † 

                       !  "#   $    %!"$& '( !"$)  **+,+ #-       ./  ./  .0,  1            2  ./    2  2, + 3              

                                                                              ‡  ¶      §        ∗



ACS Paragon Plus Environment

Nano Letters

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

                  

                  

                                   

                                         !     !"          

            !  !                         !                                       #     

       $       

            

     

                       

                                  



ACS Paragon Plus Environment

Page 2 of 26

Page 3 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Nano Letters

 

                                        !      "                      

     "        



#  $    " 



      %          "      &       " %              '"                     " " 

(         "      

)               

 

      





  

*       

     

"   

       "        +  ,   #     " "             #-   "   (( "  

 

&    "   "       

                   

       



#       ,     

                                        



!       %                 "   "    .   ,                            " $

             /*           

0-- 0/ 0-&       



       

                   "      "                 "   #            "     

  " "     

1

ACS Paragon Plus Environment

Nano Letters

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 4 of 26

           

   "  ) "   

 

             "   

    "    "   



           %     $   "               

(                                      #-    " )             02         

 /*  #-    " "         %      

       

)  3      " 

         %  "   +     )    #-          "             0--  "   0/       0-&              "   4         



               "   , #-        #     02  "           "  #-   "   

       "        "                 "       

3 

02   

       "        

        /*  #-                 #-   "   )     02           

    02 %            

         #   "     02    "      

   "     "         # 

      #- 02 

     $

    "    $    02          " 

                    0       %       %     3*

        5

ACS Paragon Plus Environment

Page 5 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Nano Letters

     " $            



(

  $                      02   "                 "  

           

                          &          02   

4 6

 "         " 7 )                0-& "   6 &2  "  - 0.2 0.8 &2    02         "  "           &2     "  02    &2   %  %      8 9        02            02    - 0.2 0.8 &2           )"             "    (    %      1 5    #  02                4  "        -     "  4    &2 '$      0-& "  

 

"   " ) 

#      

       '$           #  02    :

ACS Paragon Plus Environment

Nano Letters

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 6 of 26

   %           4

 ; 

  %                "       " 02   "  '$ #  02 

     &2 "      

   $  %  %     "    #  $

   02     '      &2 "

     "  



      &2    "

    " "     "       %    02 4

   02           '$   

   02     -       #        " 02  

  $    & "   #   '$      " $  

  0-& "             &?2 >& "                   

   "    

02   4 1 "  02   "    "           - &2  &2 

       02 %  #   "    

                     

 "       "   



               

  

#                               

 

.    +     

              4 1   " )     8

ACS Paragon Plus Environment

Nano Letters

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(a) before annealing

Page 10 of 26

(b)

(c)

(e)

(f)

MoSe2 WSe2 10 μm

(d) after annealing

                    



   "  7 )  02  $)     - &2 >&2  

4 16

   "    &?>& "   " 0-&

                7 )  02  $)                @◦ /                 $ "           "   )     @ µ 02      %      8 9         "             @◦ /    

       

  - &2            " 

  &2                                   "                     $   "      " "   $)         4 1 #   $        "        "    



/ 

  $)   % "       4 1                   $                 #             $        

    "                    

@

ACS Paragon Plus Environment

Page 11 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Nano Letters

        

#         "       02       4 1  &"       

          &2       

"               #        02      "           " - &2  &2 

                #    % 

     02           )  

      



    &2 

       )    

   " - &2  " 02   " "                    $    4 1  #         " 

         $   4 1    .   "                   "     02   4 1 

                    

#           #-   "                          +    



#  $

 " "  

         4 1         "    



         

   - &2 >&2  

          =   //     "  8@@     02                           

    K    #-   "                

(      4 1          

                          "   ""   (                     

 #-   "     "              

ACS Paragon Plus Environment

Nano Letters

(a)

WS2

(b)

(c)

MoSe2 10 μm

(d)

MoSe2

(f)

(e)

I(PL) (kcts/s)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 12 of 26

30

WS2 before annealing after annealing (x5)

x30

20 10 0

640

720

800

Wavelength (nm)

           

   ! 2 "#!2         " 7 )   02    - &2 >&2     4 56

"            " $    0-&    %  

  &?2>& "   #                    '$  $     7     - &2 >&2       - &2    

 " $  - &2 >&2                7 )   02           02

        "  

 " $         #          $       "         " 1@                         " :    "   )     @ µ 02      @

%      8 9   

       '$            



4 5   " )    02 "    - &2 >&2     

"    &?2 >& "     0-&  7   $ "    #  02 

              &2 02   

               - &2



#                 )  

      

    "       02   4 5     

        &2       02                                02      )    $ 02   

ACS Paragon Plus Environment

Page 13 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Nano Letters

4 5     02         "  

 " $         0        &2 02     

        - &2

3 $  

        &2

02     "     )  %        =        



#       &2 $  

"    

             "      "   

 

#       $  B@@                    #  

         ) "        "   "      4 5  3 $ - &2 >&2    "          "  - &2 >&2                       ,     * "      - &2



#                   $   " 

         02  )  4 5 

#  02   

     " - &2  &2         =    "            

            

#  02   "                 

          "     4 :    " )     - &2 >&2       /*     C       $        &2    &       #-        ++                "   

 "     ) "          &2 '$   "          - &2             4 : " 

 02          

        " - &2  &2

 " 02     02      "    )     1

ACS Paragon Plus Environment

Nano Letters

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 14 of 26

4 :6                 ! 2 "#!2         7 )     - &2 >&2     

"    &?2>&

"       /*                      &2 '$   "       $ " 

     (  $             "          - &2        "  " 02              02 %          $   C    @ %      8 9     02          "              "     # 

      "            "     #  " 

  "              02  

   

    #    02 %                        "    05  0:  $   

          0 01

&     02      "

      02  "     " 

          .         - &2    "     &2     

 

#      " 

     

(R + G + B)/3N    N   "        R G  B 

          "     "  @  :: #    5

ACS Paragon Plus Environment

Page 15 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Nano Letters

" 

              $        ≈@◦      :   02               

(   "  )        "   02               "     

                      02   4 :     + 02

         0 0:         

  - &2    &       

            02     "    /   

  - &2       "           02  )                 (  

   02 %  "                          - &2      $  &        

  
& "     1@@  $ &?2  4      "   - &2            "        "      &2  - &2 '$   0--

       &   (         

     !  

?   )    #-     "     "   C                  C 02        "    - 0.2 0.8 &2 C    02     - &2 >&2     "       C         &2 

    - &2 >&2     C           /* - &2  - &2  &2   

 "      " 

#      "        ( 

   

!"  

#    $  )     ;0&!/  ;0>-@